Anyone know if this has been tried?

[Rumpy Pumpy]

Rather than having a pipe with a slot to provide water flow across the screen, has anyone created a waterfall effect which uses a chamber (acrylic or plastic box), into which water is fed or pumped and which would overflow over one (slightly lowered) side of the chamber upon which the screen material would be fastened?

The water would then flow into a sump to be pumped back to the display tank or directly into the display if the scrubber were to be placed above the tank.

This could only be one sided but might eliminate issues with the slot clogging, uneven flow across the screen, and spraying & splashing.

Depending how the screen was fastened it might make removing the screen for cleaning quicker and easier too.

Thoughts?

[SantaMonica]

That is a horizontal scrubber.

[Rumpy Pumpy]

No, it would be vertical, kind of like this...

https://lh3.googleusercontent.com/-r-wPINOKjLc/TiNKK8mUPNI/AAAAAAAAAD4/-kSkwJkpDMc/boxscrub.JPG

The water is fed into the box, and when it reaches the level of the lower side, it spills over, creating a curtain of water over the screen (shown in green)

[dtyharry]

That looks like a really good idea. You could have the bottom of the screen just touching the water to prevent splashing and it would be great as a hang on side or back. You could even use the water in the box as a little refugium. Only thing is is if was a hang on side fixture you would have to make sure light fixture was really secured as it would not be far from water surface of display tank, unless is course you lit it from external side.

[Rumpy Pumpy]

I mocked up a small semi-running model this morning to see if I could find any pitfalls

Used an old sump box, and little pump and a bit of old screen held on with a bulldog clip

Here's a short video of it

http://www.youtube.com/watch?v=ajAevR853Tw

The pump is only running at about 130 gallons per hour (it's the only spare pump I have) and the screen is 14 inches long so it would need 3 or 4 times this flow according to Santamonicas 35gallon/hour/inch guideline, but you can see from the vid that it does cover the screen evenly and cleanly, there is no splashing or spraying and no slot to clog up.

Obviously the bulldog clip would be no use so it'd need some method of holding the screen in place/ I thought perhaps a length of plastic channel (kind of U-shaped in profile), fixed along the top edge of the screen that could just hang on the acylic edge with the water pouring over it. Maybe it could be fixed to the screen by welding or by some form of adhesive?

The only potential problem I can see so far is that the "curtain" of water is very smooth, with no turbulence or air bubbles in it as it falls. This makes it quiet but I wonder if it might have a detrimental effect on algae growth (I'm assuming that having air bubbles in the water will increase the CO2 available to the algae cells).

On the other hand, having a smooth bubble-less curtain of water flowing over the screen may mean that more light penetrates to the algae surface? (I'm guessing that bubbles in the water will reflect some of the light away from the screen)

I think I'm going to build one of these and see how it runs in practice.

[DesignsOnline]

It could be a good workable solution for an in-sump design , but you would only be using one side of the screen so it wouldnt be as effective as other designs...

[dtyharry]

Don't think the smooth flow is an issue, all the co2 used would come from the water. If all the co2 is used up the algae uses bicarbonate which is why you need to keep an eye on your dkh level. Similarly I don't think bubbles/nobubbles is an issue, just make sure the screen is nice and rough. I used to have a hang on refugium with chaetomorpha, this addition would be brilliant.

[Rumpy Pumpy]

It could be a good workable solution for an in-sump design , but you would only be using one side of the screen so it wouldnt be as effective as other designs...

I'm not convinced that's true.

The advantage of a double sided screen is that you can fit the same screen width into half the linear space (although you need more space in the other direction to accommodate two sets of lights). I have seen it claimed that some of the light from each side penetrates through to the other side but I don't really see how that can be. Maybe when the thing is brand new but once it has a good covering of algae on it, any light penetration through the screen is going to be very minimal I would have thought.

Both one sided and two sided designs have their pro's and con's, I guess it depends on what space you have available and what your preferences are as to which is "the best".

[Rumpy Pumpy]

Don't think the smooth flow is an issue, all the co2 used would come from the water. If all the co2 is used up the algae uses bicarbonate which is why you need to keep an eye on your dkh level. Similarly I don't think bubbles/nobubbles is an issue, just make sure the screen is nice and rough. I used to have a hang on refugium with chaetomorpha, this addition would be brilliant.

Cheers.

I'm going to build a false glass back into a 3 ft long spare tank I have next week. It will have a 22 inch long "lowered" section in the middle onto which a 22inch long screen (which I have laying about) will hang.

The lighting I will have to have a think about.

[rygh]

Seems like a pretty good idea.
Only one sided, so half the surface area, so needs to be twice as big.

It will be interesting to see what happens when algae grows on the lip.
Since there is no pressure, it might build up, and flow could become uneven quickly.
On the other hand, the overall flow will not drop off like a clogged slot.

You might end up with a bit of dead crud on the dark side of the screen.
That was a minor annoyance with my old semi-horizontal.
Although amusingly, you can end up growing coralline algae there.

[Rumpy Pumpy]

It will be interesting to see what happens when algae grows on the lip.
Since there is no pressure, it might build up, and flow could become uneven quickly.
On the other hand, the overall flow will not drop off like a clogged slot.

Yes that's a possibility.

The lip will be smooth though so it shouldn't build up as quickly as on the screen and a quick wipe when cleaning the screen should keep it down.


You might end up with a bit of dead crud on the dark side of the screen.
That was a minor annoyance with my old semi-horizontal.
Although amusingly, you can end up growing coralline algae there.

I had that with my original horizontal one too. Used to get loads of pods living under the screens as well.

[Gigaah]

I like the idea of trying to find another method to get water on the screen. Pipes are hands down the easiest thing but they are not perfect.

The basic idea can be adpated to a 2 sided design. This is a sketchup of a design that is pretty close to what I'm using on my nano. It has been modified with using an overflow into it in mind.

The hole is where the overflow would be plugged into. The whole unit is 2"x2"x10"L. Same concept..the container fills then the water flows over the edge. You could easily shade the slot by extending the acrylic over it and painting it. The only issue with the basic design is that it has to be level..or it wont work right. You can use super glue to glue acrylic together. It works extremely well..in fact other than weld-on..its the only thing that works good at all.

It should provide a uniform flow rate over the length of the screen...which I've found is the first issue I deal with using a pipe. and 2nd it will be easy to shade the slot from light because its square..just glue some extra pieces of acrylic on the outside of it not touching the water stream and paint them.

[Rumpy Pumpy]

That's clever. I like that.

I'm not sure your average hobbyist would have the skills to build something like that though. I don't think I do anyway.

You could get around the algae blocking the slot issue by making the whole thing from black acrylic and having a short flat piece extending below where the screen emerges from the slot to shield it from the light there.

I'm not sure where or how you're securing the screen from your plan or how it would be removed for cleaning?

[Gigaah]

I didn't really get that far into the idea. It was just more to represent the concept i just drew it up in Google sketch-up quick. I'm sure a little thought would yield a good solution.

you could paint it black with krylon. black acrylic isn't always easy to get. And krylon has been used in contact with saltwater in reef aquarium in several occasions that I've known and has no issues. I know it sounds all sorts of wrong..but I won't argue with those that have done it and still have thriving tanks.

I agree its not for your average hobbyist. But a piece of .093 acylic, a plastic knife(score and snap), some gel super glue(works good), and its probably something that fits into what your DIY crew could probably do. The pvc pipe and slit you just can't beat for ease of construction tho..no doubt about that..dead simple.

[SantaMonica]

Ahh... you meant one of these...

http://www.radio-media.com/fish/NanoBuiltIn.jpg




Don't think the smooth flow is an issue, all the co2 used would come from the water. If all the co2 is used up the algae uses bicarbonate which is why you need to keep an eye on your dkh level.

Correct.


The advantage of a double sided screen is that you can fit the same screen width into half the linear space

That's part of it. But the real power of double sided is in keeping the roots alive longer. Since they get light from both sides, they stay attached. My estimate is it provides about 100% more filtering for the same amount of watts on a single sided setup.


I have seen it claimed that some of the light from each side penetrates through to the other side but I don't really see how that can be.

Not "to the other side", but "to the screen", which means... "to the roots".

[Rumpy Pumpy]

Ahh... you meant one of these...

http://www.radio-media.com/fish/NanoBuiltIn.jpg


Yep! That's the idea. And here was I thinking I'd thought of it first! :?

Do you happen to know if anyone's actually built one yet and if there were any problems not mentioned so far?

[kotlec]

Thats exactly what I used from day 1. It needs bigger screen, and thats the only drawback at my point of view. Very happy with setup overall. If I would do new tank, I would do same design again - no doubt.
In my case waterfall takes start directly from tank overflow and goes in to the back chamber, so eliminating one additional container. No problems with leveling as overflow comb evens up any small unevenness. Not a single pipe used as well (except return pump).

Take a look :
viewtopic.php?f=2&t=1242 (http://www.algaescrubber.net/forums/viewtopic.php?f=2&t=1242)

[Rumpy Pumpy]

Thats exactly what I used from day 1. It needs bigger screen, and thats the only drawback at my point of view. Very happy with setup overall. If I would do new tank, I would do same design again - no doubt.
In my case waterfall takes start directly from tank overflow and goes in to the back chamber, so eliminating one additional container. No problems with leveling as overflow comb evens up any small unevenness. Not a single pipe used as well (except return pump).

Take a look :
viewtopic.php?f=2&t=1242 (http://www.algaescrubber.net/forums/viewtopic.php?f=2&t=1242)


Excellent.

Works then!

I've put mine together today. It's built into a 3 ft tank and the screen is 22 and a half inches wide.

Tomorrow when the silicon's cured, I'll give it a test run.

I found a way of hanging the screen so that it stands slightly out from the glass wall. Used a length of plastic extrusion shaped like a capital E in profile. The screen is wedged into one channel (I'll silicon it in once it's tested and the screen roughed up) and the other channel sits on the edge of the glass. It just lifts off easily for cleaning.

I'll probably use some 24 inch T5s to light it but haven't decided how many yet. It'll be going under a 55 gallon tank to begin with so it won't need to run at anything like it's potential.

https://lh5.googleusercontent.com/-IMhGVrrQIW0/TiNKKF_F5sI/AAAAAAAAADg/ZZKuYwhhO0k/2011-07-04%25252016.39.22.jpg

https://lh3.googleusercontent.com/-OUzbstNpCTg/TiNKJ5Zov7I/AAAAAAAAADk/LZRpuuxQ5iM/2011-07-04%25252016.39.43.jpg

[Rumpy Pumpy]

Test for flow

http://www.youtube.com/watch?v=3TUYJ5TUVHE

This pump is rated at 5000 litres per hour, it's a year old, has just been cleaned and there's no head to speak of in this test so I guess it's running at around 4000-4500 lph, say 4250 which is about 935 gal per hour (1120 in US gallons), making a little over 40 gals per hour per inch of screen width.

It's not quite as quiet as I had imagined but there's no splashing at all, whether that will remain the case with a screen full of algae I don't know. I suppose I could add a splash guard pretty easily if it does.

Thoughts?

[itzrulez]

i think this video, shows something like you want...
http://www.youtube.com/watch?v=ajAevR85 ... re=related (http://www.youtube.com/watch?v=ajAevR853Tw&feature=related)

[Rumpy Pumpy]

i think this video, shows something like you want...
http://www.youtube.com/watch?v=ajAevR85 ... re=related (http://www.youtube.com/watch?v=ajAevR853Tw&feature=related)


Cor yeah! That's a good one isn't it!

[itzrulez]

ow, sorry...
I didnt see that was uploaded by you like the other...

[Rumpy Pumpy]

ow, sorry...
I didnt see that was uploaded by you like the other...


LOL :lol:

No worries mate. Easily done. :mrgreen:

[Rumpy Pumpy]

Lights on

https://lh4.googleusercontent.com/-tCcnsgVKnMs/TiNKKJicJqI/AAAAAAAAADo/Np55_jPf9U0/2011-07-09%25252012.49.47.jpg

Bulbs are 20w each. The whole thing can slide back & forth to adjust the distance to the screen.

Ordered some acrylic mirror to make reflectors.

[DesignsOnline]

Looks good, Ive just ordered a box of 40 of those.
Are you going to light the other side too?

[DesignsOnline]

By the wat the acrylic mirror bends really easily if you heat it up...

[Rumpy Pumpy]

Looks good, Ive just ordered a box of 40 of those.
Are you going to light the other side too?

No, the design doesn't really allow for that so it'll have to be one sided.




By the wat the acrylic mirror bends really easily if you heat it up...

Thanks for that. I've not used it before.

Will being a couple of inches from the bulbs make it warp do you think?

I'll stick it to some backing if that's the case.

[Rumpy Pumpy]

Chiller and scrubber/sump in carcass of new cabinet built to house them.

http://img.villagephotos.com/p/2010-9/1360140/2011-07-11%2018.52.04.jpg

Made some reflectors from polished aluminium (some old T8 reflectors cut into shorter lengths) - Didn't bother with the acrylic mirror in the end

http://img.villagephotos.com/p/2010-9/1360140/2011-07-13%2017.58.43.jpg

Lights with reflectors installed on scrubber

http://img.villagephotos.com/p/2010-9/1360140/2011-07-13%2017.58.10.jpg


Thoughts?

[Floyd R Turbo]

Looks pretty good to me! That's a great idea on the reflectors. One step better could be to find reflectors for T12 lamps. The thought being that since the reflector is made based on a lineal source, the reflector would be larger for a T12 versus a T5 for instance, since the source is wider (lamp diameter). Taking that to the extreme, for a triple-tube lamp, you have a source that is roughly 2x the diameter of a T12, so then you would want a reflector that is about 5 or 6 inches wide, but I think you would have a harder time finding one like this. And this would work for the tubular CFL, not sure how such a reflector would work for the spiral CFLs.

Plus, you would probably only see a slight (10% maybe) increase in the light power added by using a 'perfect' reflector versus the one that you are using, but I just figured I would comment about it for anyone else looking to do the same thing. If I had the time, I'd search online for various reflectors using the same principle.

[Rumpy Pumpy]

Installed and running. A bit untidy, have to sort out the cables and pipes and the rock in the sump is going in the display when it settles down.

http://www.youtube.com/watch?v=3TOQ4EpdJag

A few more bubbles than I was counting on, I will need to make a splash guard to stop the bulbs & reflectors from salting up.

Rubbed the screen on the old screen from my stop-gap scrubber. Some algae has attached to it and seems to be sticking to it so far. Dunno if that will speed up the growth process.

[Rumpy Pumpy]

Green already appearing, not even 2 days yet

https://lh6.googleusercontent.com/-L3UwHK7MWjA/TiNMe6L_8sI/AAAAAAAAAEM/ZeRe9nlh6PY/2011-07-17%25252011.36.22.jpg

[SantaMonica]

Growth is going to be good, I can tell.

[Rumpy Pumpy]

Growth is going to be good, I can tell.


Fingers crossed.

[Rumpy Pumpy]

First cleaning after 7 days

Appearance in the scrubber (added an acrylic splash guard since last update)

https://lh6.googleusercontent.com/-7XFSY1K6uWY/TiluCeB3m2I/AAAAAAAAAHw/rzmlKvGJTBs/2011-07-22%25252013.21.02.jpg

Screen out of the scrubber before cleaning

https://lh4.googleusercontent.com/-OpIVCzqP35M/TiluB1tn52I/AAAAAAAAAHs/YDIkLnwjBMo/2011-07-22%25252013.22.54.jpg

After scraping with a plastic card and hosing down

https://lh5.googleusercontent.com/-LDUEfskHU0o/TiluBeBmzFI/AAAAAAAAAHo/kR8NcfMWoVo/2011-07-22%25252013.25.54.jpg


Harvested a small fistful of hair algae from scraping which weighed 9 grams (third of an ounce) with all the water squeezed out (still damp). Not bad for the first week?

Was quite pleased on how easy it is to clean, just lifted the screen off with it's hanger, scraped squirted and replaced, took no more than 2 minutes and I didn't even have to turn the pumps off.

[SantaMonica]

Yes for a first week it looks good.

[Rumpy Pumpy]

Thanks.

I think there're a couple of areas where the screen could be rougher.

I'll give it another week to fill in and re-rough those places if they're still sparse.

[Floyd R Turbo]

Just clean it off by using a hacksaw blade, little tiny scratches will add up over time and it doesn't take material off unless you really scrape hard.

[Rumpy Pumpy]

Just clean it off by using a hacksaw blade, little tiny scratches will add up over time and it doesn't take material off unless you really scrape hard.


Good idea.

I have this vibrating saw tool (http://goo.gl/Wk7Qs) though which makes roughing the screen easy (as long as you select the right blade - note the missing piece on the lower right hand side of my screen, caused by using the wrong one).

[Rumpy Pumpy]

Second cleaning (week 2)

https://lh3.googleusercontent.com/-MCGtxBCBHdQ/TjJ6yGCwBAI/AAAAAAAAAMc/-Rp8TXrytbM/2011-07-29%25252010.03.47.jpg

As you can see the bulbs have been a little too close to the screen. I've backed them off an inch now

https://lh4.googleusercontent.com/-ymFPug5B64E/TjJ6xgzTWaI/AAAAAAAAAMY/BH9TfSIrMz8/2011-07-29%25252010.07.46.jpg

After scraping

https://lh5.googleusercontent.com/-mlAkcgqb2H0/TjJ6w-nPPRI/AAAAAAAAAMU/GwXPOOAcDqk/2011-07-29%25252010.13.57.jpg

Yield (about 5 ounces)


Did a little video this time with the lights and splash guard off to show the flow over the screen.

http://www.youtube.com/watch?v=-tvHWsBUqJg

I think the flow might be a little low, I haven't measured it but I suspect that the head loss on the return pump is more than stated by the manufacturer.

Thoughts?

[Rumpy Pumpy]

Cleaned this again today a day early as I had a pump problem in the night which dramatically reduced flow and caused a minor flood (hermit crab got into the overflow pipe) and the screen was looking a bit sad (thought I should get rid of any dead or damaged algae before it started to fall off)

Anyhow, the yield was slightly higher than the 2nd cleaning, 15 grams or so but it all looked a bit yellow and nasty (which I put down to being under strong lighting for hours last night with very little flow)

While I had the thing stripped down I did a flow test on the sump inlet (which I suspected was lower than it should have been) and found that I was only getting 900 litres per hour, from a pump rated at 5000 lph (Eheim Compact 5000), but with a 5 foot head (supposed to give nearly 3000 lph at that level according to Eheim).

I also have a little pump circulating water through a chiller which discharges 900 lph into the scrubber flow so the screen has only been getting 1800 litres per hour on a 56cm wide screen which is only 32 lph/cm (against the 60 lph/cm guideline).

I've simplified some of the plumbing (took out a couple of 90 degree bends and shortened the pipe into the tank a little) and am now getting 1450 l/hr from the Eheim making 2350 litres per hour across the screen in total (42 lph/cm)


Obviously I'm going to need a better pump.

[Floyd R Turbo]

What is the ID of your return plumbing?

[Rumpy Pumpy]

What is the ID of your return plumbing?


About 22mm I think, it's 25mm (about 1 inch) pipe

[Rumpy Pumpy]

Actually, now I think of it, there is a hose joiner thing on it which probably restricts it further. I'll have to have a look at that and see.

Thanks Floyd, you might have saved me getting a new pump!

[Floyd R Turbo]

It's a common problem that comes up when you build a scrubber. Unless it's critical for your tank (like heavy SPS) most people think their flow is fine, when it's really not. The Mag 12 I was running should have been pushing 1100 GPH but was only pushing 433 with a clean pump. I was running 3/4" return, upped it to 1.25" (still a 3/4" bulkhead) and it went to 780. It's simple fluid dynamics, the smaller diameter pipe, the faster the water has to move through the pipe, thus more friction and reduced flow rate. Head pressure on the pump is not a function of the diameter of the piping, it's a function of pressure. The weight per horizontal square inch of water in a given water column height does not change, only the square inches itself. This means that the calculated head pressure resulting from a given column of water, ignoring friction, a 4" PVC pipe is identical to that of a 1" pipe. You can put the biggest plumbing you can feasibly install.

[Rumpy Pumpy]

Just took the hose off & measured the connector ID

It takes it down to 15mm -vs- 20 mm for the rest of the plumbing :o

So that will be going tomorrow.


Thanks again Floyd.

[Floyd R Turbo]

That is definitely your problem. Bump that bad boy way up, you'll be shocked.

[Rumpy Pumpy]

you'll be shocked.

:o

[SantaMonica]

Yes throw out anything dead.

[Rumpy Pumpy]

That is definitely your problem. Bump that bad boy way up, you'll be shocked.


Dunnit.

The flow from the Ehiem is now about 2050 lph, which is not far off that Eheim claim (I misread the chart, it should be giving about 2300 at this head)

So I have 2050 from the display plus 900 from the chiller return totalling 2950 litres per hour across a 56 cm wide screen giving 53 litres per hour per cm

Which is 35 US gallons/hour/inch or 29 imperial gallons/inch. Should be ok I guess.


Thanks again Floyd, saved me buying a new pump.

[Rumpy Pumpy]

Went away for a week, did a clean the day we left (Sunday before last) and was expecting some nice growth on my return.

Was a bit disappointed.

There was growth, about the same yield as the previous week, give or take, and a few patches of longer tougher algae which I hadn't seen much of before, but most of the algae was very light green and soft/slimy, not quite yellow, but washed out green.

The tank wasn't fed while we were away so I guess that's an factor but there is some type of hair algae (or maybe green cyano?) in the tank (that nothing will eat) which I was hoping 7 days without food would reduce either by starvation or by the herbivores in the tank being forced to eat it in the absence of anything else. But it has actually increased while we were away, by quite a lot.

Didn't take any pictures as the battery was flat when I cleaned.

Anyhow, I've read on here that pale green can mean low iron so I've put an iron nail in the sump & will monitor what happens with that.

[Floyd R Turbo]

No feeding for a week is what did it. Remind me, do you have fish in the tank?

[Rumpy Pumpy]

No feeding for a week is what did it. Remind me, do you have fish in the tank?


Yes, a yellow tang, a coral beauty, four chromis & a pair of clowns (plus CUC).

I think you're right about the no feeding, but can't explain the increase in the green hairy stuff in the display tank.

[Floyd R Turbo]

Yow. I'm surprised they survived. Why didn't you at least get an automatic feeder and have it drop a few pellets in every day?

[Rumpy Pumpy]

Yow. I'm surprised they survived. Why didn't you at least get an automatic feeder and have it drop a few pellets in every day?

I've got one, but after consulting on another forum decided to leave it for a week.

There's loads of pods in there and I was hoping the herbivores would graze on the green hairy stuff, but they didn't

None of the fish appeared in any worse condition than when I left them.

[SantaMonica]

Sounds like lack of flow. Only add iron if you can't add flow.

Do the nail thing with caution... might contain other metals that you don't want, and they will reach the corals before they reach the scrubber.

[Rumpy Pumpy]

Sounds like lack of flow. Only add iron if you can't add flow.

Do the nail thing with caution... might contain other metals that you don't want, and they will reach the corals before they reach the scrubber.


The flow's the same as it was when I left it. And more than it was in the first couple of weeks (see up the thread). It's getting about 52 litres per hour per inch (35 US gals)


On refection you might be right about the nail. I'll remove it & get some chelated iron.

[Rumpy Pumpy]

Fluffy green stuff growing in my display which nothing will eat and which seems to be increasing despite the scrubber

https://lh4.googleusercontent.com/-AUvwJZpuaHg/Tk0NYQa1wNI/AAAAAAAAAPs/YU0Iwt6Zdf8/2011-08-18%25252014.00.25.jpg

https://lh5.googleusercontent.com/-lJdvyloqYI8/Tk0NcOjj9II/AAAAAAAAAPw/Q3WvX7o5QRU/2011-08-18%25252014.00.15.jpg

https://lh6.googleusercontent.com/-fXLVH66A-TI/Tk0NU8jdOgI/AAAAAAAAAPo/OhMe2VRh6KA/2011-08-18%25252014.00.43.jpg


I don't think it's any type of hair algae as nothing will eat it, not even hermit crabs.

I suspect that it's some sort of green cyano (although it seems to prefer areas of high flow)


Any thoughts?

[Floyd R Turbo]

Most definitely GHA and most definitely not cyano. Cyano is slimy and usually grows like a mat, coating rocks, gravel, etc. The crabs/snails won't eat the GHA probably because it's too long. Most snails won't eat anything over about 1/2" long IIRC. This could be a result of the week of no feeding but not sure. Should be out-competed eventually. Manual removal may help.

[SantaMonica]

Either you scrubber is getting weaker or stronger.

If weaker, you should be getting thin nuisance algae all over the rocks, sand and back wall.

If stronger, you should be getting no algae all over the rocks, sand and back wall, except for these current blocks of algae which are surviving from the P leaving the rocks. I think this is the case because they are at the peaks of rocks, which is always the last place for P to removed from.

[Floyd R Turbo]

I agree, looks like it's getting stronger, or at least finally catching up to the nutrient load of the tank.

[Rumpy Pumpy]

Thanks for the replies.

The "getting stronger/nutrients reducing" idea figures as (after input from Floyd) I was able to increase flow shortly before this stuff started to take off again and that was just before leaving it for a week with no feeding.

There is no slimy stuff on the rock or elsewhere.

I'm still not convinced that it's GHA as I'd have thought that the Tang and the Coral Beauty would have demolished it if it was. They both peck away at the rest of the rock all the time and used to pounce on bits of GHA which broke off of my earlier scrubber.


I have read of a type of cyano which looks like hair algae and likes low nutrients but can't find out anything else about it so far.

Anyhow, it's doing no harm as far as I can tell so I'll leave it for now and see if the scrubber can starve it out over the next few weeks/months.

[SantaMonica]

Yes, it's classic green hair algae, in perfect 3D mode. Tangs don't like it that long. Neither do lawnmowers.

[Rumpy Pumpy]

Ripped most of it out now & will repeat until it stops

[Rumpy Pumpy]

Cleaned again today.

Not bad but no increase in the yield and I'm not getting much hair algae on the screen (except on the lower semi-submerged section).

I am however getting several types of it on the bottom of the sump, the sides of the sump, the rock-rubble in the sump, the pumps, the glass chamber behind the screen (quite a lot, which I'm ok with as I consider it a refugium).

Cleaned it all out today except the stuff in the chamber.

The screen algae though is mostly slimy stuff, quite thick, and somewhat green (light olive coloured), but not much hair in it.

My flow I think is ok, could be better but certainly a lot more than on the other surfaces which are growing GHA

My screen is very rough.

I suspect that my bulbs have been too close to the screen. I'm using 5 x 20 watt CFL sticks for a 22.5 x 8 (above the water line) inch wide screen which makes 0.55 watts per square inch. (Maybe I should have gone for 15 watt bulbs instead?)

For the last three weeks they have been about 2.5 inches from the screen (closest point of bulb surface to the screen surface) so I've backed them off today to 4.5.

Will run it for a week and see how it goes.

[SantaMonica]

If the growth is not yellow, then the lights are not too close.

If the growth is dark, the light needs to be stronger. Or just wait longer for the nutrients in the tank to come down.

Stronger light, or less nutrients in the water, will make green growth.

[Rumpy Pumpy]

If the growth is not yellow, then the lights are not too close.

Thanks again for the input SM. It's not yellow, just washed out olive green slimy stuff.



If the growth is dark, the light needs to be stronger


There's 100 watts for a 55 gallon tank with good reflectors and they were 2.5 inches from the screen. How strong can they be?

I'll run it backed off to 4.5 inches for the week and see what happens. I was getting GHA on the top edge of the screen, the bottom part and elsewhere in the sump, but not on the section of the screen closest to the bulbs (except a few tiny patches)

Wish I took a photo of it now, but here's a vid of what it looks like now (note the GHA in the chamber behind the screen) Does this flow look enough? (it's 52 litres per hour per inch (just over 35 US gallons)

http://youtu.be/gjlTKXcOr3Y


Thanks again.

[SantaMonica]

Ok I see the pattern now... it is burning in the middle. This would be the yellow I was talking about.

[Rumpy Pumpy]

Little update

Seem to be getting a bit more green patches in the middle section of the screen with the lights backed off to 4.5 inches, but it's still mostly olive coloured.

This is 4 days growth.

https://lh3.googleusercontent.com/-Bkoajx07ASQ/TlZE7BVYPsI/AAAAAAAAAfY/CM0f31qmPlo/2011-08-25%25252013.48.26.jpg


Got an Fe test and it is reading zero - it's colour chart shows down to 0.1 mg/l (and up to 1.0) but it's getting no reading at all, so I've bought an iron supplement and am starting to raise it (I'll test as I add it incrementally to be sure that it's not just a duff test)

While I was at the LFS I asked them to test my water (they have more accurate tests than mine, which all show zero) and got these results, which seem fine.

No3 <0.5 ppm
NH4 <0.25 ppm
No2 <0.01 ppm
PO4 <0.02 ppm

I think the low nitrate & phosphate suggest that you were right about my display tank hair algae being due to leeching from the rocks SM.

I'll be interesting to see what effect the iron supplement has on the algae growth and colour.

[Floyd R Turbo]

I would worry that you have ammonia in the tank. Although, just because an LFS has test kits doesn't mean they're more accurate. I've seen LFS using API Nitrate kits and not shake the #2 bottle, then hold it horizontally instead of vertical, and compare it to the chart right away, then compare it to a faded out color chart.

[Rumpy Pumpy]

I questioned that. He said that that was the lowest the test goes to so if there's no reading they just say that it's lower than that & that it's probably near zero. My api ammonia test says 0 anyway.

[Floyd R Turbo]

Weird. What test kit did he have that was unable to show the difference between 0.25 ppm and 0.0 ppm ammonia?

[Rumpy Pumpy]

Weird. What test kit did he have that was unable to show the difference between 0.25 ppm and 0.0 ppm ammonia?

Not sure.

Might have been Salifert

[Rumpy Pumpy]

Latest cleaning (5th I think)

https://lh5.googleusercontent.com/-D3gScgcubys/Tln0VPQ76KI/AAAAAAAAAgs/uKUBRDxtg8k/2011-08-28%25252008.25.02.jpg

The green is filling in a lot more now with much more long strands of hair type stuff. It seems tougher too, more was left after scraping.

The yield was down a bit though - I have been getting 140-170 grams (5 to 6 ounces) per week of drained gunk, but this week it was only 110.

I've pushed the lights forward about an inch, after backing them off 2 inches last time.

Continue to dose iron - Added quite a lot but have only been able to get the test up to 0.25 so far, aiming for 0.5. At this rate though it's gonna be a costly exercise, unless it's "filling in" and will eventually find a level. Have to find a cheaper source of iron.

Feeding a bit more this last few days, 2 cubes a day plus a bit of flake and will continue with that.

[Rumpy Pumpy]

Latest cleaning (6 days this time as I'm not around tomorrow)

https://lh3.googleusercontent.com/-HxnrSWYKkvM/TmHcI9jeKQI/AAAAAAAAAkQ/esB_BY8nSgk/2011-09-03%25252008.06.37.jpg


Bit more green, yield the same as last week though, 110 gram drained.

Perhaps that is all I'm going to get from the amount I'm feeding?

At the moment I'm feeding 2 x 5g cubes per day plus about a gram of flake (and this week have fed one 8 x 8 sheet of nori too)

So that's 70g of frozen and 7 grams of flake per week. The flake label says 8.8% moisture, so if once rehydrated it became 5 x that (a guess) weight that would make it equivalent to about 5g per pay or 35g/week, meaning that I might be scrubbing out a similar amount to that which I'm feeding in?

The hair algae in the tank appears to be receding anyway.

[Rumpy Pumpy]

Bought a Salifert phosphate test.

Shows zero (on the sensitive scale which tests down to 0.015)

https://lh6.googleusercontent.com/-XmDGmeVS4jg/TmZeq3AAQQI/AAAAAAAAAlc/z3E-gHeaH38/2011-09-06%25252018.55.03.jpg


Must be working than.


GHA still growing on the rocks and on snail & hermit shells too (as phosphate comes out I assume). Anyone know how long that lasts?

[SantaMonica]

A few months.

[Rumpy Pumpy]

Thanks

[Rumpy Pumpy]

Filling in nicely now

https://lh3.googleusercontent.com/-SnideDKvjrc/TmsdUtLBsUI/AAAAAAAAAmo/lPFvL137rWY/2011-09-10%25252008.56.14.jpg

Yield's back up too

https://lh6.googleusercontent.com/-7x2YO7JXwg4/TmsdPFTWiiI/AAAAAAAAAmk/eCw_xmz1U2g/2011-09-10%25252009.12.50.jpg