PDA

View Full Version : The project begins!!



ThePisces
10-10-2009, 12:28 PM
Started my HORIZONTAL scrubber today!

I have the tray made on which the screen will sit which is 22 inches long and made from twin wall polycarbonate sheet that is used for roofs on conservatories, greenhouses etc.It has side walls of about an inch high to keep the flow moving in the right direction. It's just over the width of the plastic canvas 10.5 inches so a potential scrubbing area of 231 sq inches on a single side! Also in the process of making a splash proof light housing that will hold up to 5 possibly 6 low energy bulbs. I have designed it so I can add more bulbs if need be and it won't take up any more room as a result. I think I shall start with 3 x 18w maybe two ( 100w) and go from there?

It can be placed at the same angle as the tray and at any height above the tray from 1inch to 12inches with full coverage of the 13.5 x 10.5 inch screen! Am going to see how one screen performs but can easily add more screens either sandwiched or end to end to make the full use of the tray. All are held in place by a plastic pin which you simply push the screens on through a hole which is in the screen itself, so there is no restriction of the flow of water being emmited onto the screen, easy as pie!

Still waiting for the postal system to get back to normal as still no sign of the pipes I ordered a week ago this Monday! When the pipe arrives I was pondering on the idea of pointing the flow of water coming out of the pipe up the incline which will be placed about two/three inches down from the start of the slope and so 'hopefully causing the water that is coming down meeting the water going up a more turbulent flow, hopefully slightly pulsed? Hope that makes sense? We shall see!

Will post photos before I install it and after providing I can work out how to upload the piccies?

Happy Scrubbing everyone!

AlgaeNator
10-10-2009, 09:50 PM
I just spent 2 hours explaining how to upload and post picturers to the web/forums.. here...

I am requsting full Mature scrubber pics on this thread, and my first 4 posts are trying to help people learn how to upload pictures and post them online in this forum or anywhere else, so we can get lots of pictures on it....

HTH

viewtopic.php?f=2&t=346 (http://www.algaescrubber.net/forums/viewtopic.php?f=2&t=346)

also when you are up and running come back to my thread with your new upload skills take some nice shots of your mature scrubber and postem!

ThePisces
10-11-2009, 02:08 AM
Ok when all is assembled and running I will get some nice piccies for all to see. Will get the 'Other half' to sort the uploads if i can't sort it as she's the computer boffin round here.

The Pisces

ThePisces
10-12-2009, 02:46 PM
We have lift off! All assembled and running. My horizontal scrubber has been running for about 1 hour and 30 mins( time now 22:43 GMT) All looking good and I have fantastic turbulent flow over a full 22in x10in screen with 54w of CFT (300w equivalent). Practically no splashing, and noise is barely detectable. Have lights to within 4 to 5 inches an due the the white acrylic box housing the lights have a very even spread of light. Had to do a bit of fine tuning today regarding how to get a good spread of water from the outlet pipe but cracked that problem.

Have taken some photos so will try to get them posted tomorrow with a few more details of how I went about my design for a sump based horizontal scrubber.

Thanks to all of you on this site who have given me the ideas (and challenged my approach,thanks SM) for what I hope will be a very effective(and very cheap) design for a H.A.T.S ..Horizontal Algae Turf Scrubber....with a slight incline of a about 15 degrees.

I will try to give a day by day account of how the scrubber develops and how the aquarium parametres change.

The Pisces

ThePisces
10-13-2009, 02:16 AM
Ok well have my horizontal ATS running now and have a few piccies to share. It's been running for 12 hours now and all going well. Did a few fine tweeks this morning so now 100% happy with it. I reckon it has cost me less than £5 ($10) to make and that includes the CFT which cost me 49p for five 18w (100w) low energy at Wickes ( UK) Have to say I thought they were cheap but just yesterday I nearly fell over in disbelief when I found them even cheaper at Morrisons....get this.....five for......20p..I kid you not! I bought enough CFT's to last me a lifetime!

Anyway here are a few photos of my horizontal (15 degree incline) ATS.[attachment=2:19hp45eu]Lightbox additional CFT.JPG[/attachment:19hp45eu][attachment=1:19hp45eu]Lightbox Bottom View.JPG[/attachment:19hp45eu][attachment=0:19hp45eu]Lightbox Rear view.JPG[/attachment:19hp45eu]

Ok lets see if this works, more to follow...

ThePisces
10-13-2009, 03:05 AM
More photo's....[attachment=2:hc6fztfo]Lightbox Top View.JPG[/attachment:hc6fztfo][attachment=0:hc6fztfo]Lightbox with vent holes.JPG[/attachment:hc6fztfo][attachment=1:hc6fztfo]Lightbox with reflector fitted.JPG[/attachment:hc6fztfo]

More to follow.....

ThePisces
10-13-2009, 03:12 AM
[attachment=2:2idw5nmi]Lightbox,screen and outlet pipe.JPG[/attachment:2idw5nmi][attachment=1:2idw5nmi]Outlet pipe and screen.JPG[/attachment:2idw5nmi][attachment=0:2idw5nmi]Outlet pipe with anti-splash guard.JPG[/attachment:2idw5nmi]


More to follow......

routestomarket
10-13-2009, 03:14 AM
I like it!

Only suggestion is get some mirror or other reflective into the light box. Any light coming through the box is being wasted.

Keep up the good horizontal work! :)

ThePisces
10-13-2009, 03:18 AM
Thanks, have added baking foil as a reflector. The opaque white acrylic reflects a great deal of light on it's own and disperses the light very evenly across the screen. More pics to follow.

The Pisces

routestomarket
10-13-2009, 03:19 AM
Oops, I think our posts crossed in the ether!

Now I think it looks great! I like the way your assembly room is full of clutter! Thought it was just me! ;)

ThePisces
10-13-2009, 03:28 AM
[attachment=0:29nqtkhp]Tray,two screens.JPG[/attachment:29nqtkhp]

I have one more photo of the screen/tray prior to installation but the file is too big...ahhh anyone no how to reduce the file size?

Hope it's looks good so far. Mechanics of it work far better than I though it would. Sitting patiently now and waiting for that turf to grow!

If you look at the side walls which keeps the water where it needs to be, you can see the waves up against it and volume of water that is being produced.

kcress
10-13-2009, 03:31 AM
I'm not getting a good feel of how the whole thing is set up. Got a pulled back shot that shows everything?

ThePisces
10-13-2009, 03:34 AM
I'll see what i can do...just got my camera phone which isn't the greatest. I'll get a photo of the outside of cabinet so you can get an idea of how compact the whole thing is.

The Pisces

ThePisces
10-13-2009, 03:56 AM
[attachment=1:1slhppo6]External view left hand.JPG[/attachment:1slhppo6][attachment=0:1slhppo6]Light unt showing boths screens.JPG[/attachment:1slhppo6][attachment=0]Light unt showing boths screens.JPG

ThePisces
10-13-2009, 03:59 AM
I have two photo's whose file size is too big, tried to zip them but wont work on here.

ThePisces
10-13-2009, 04:07 AM
Lower screen is just 'laying there' at the moment. Need to get another plactic pin the attach same as upper screen. Note the plactic peg which holds upper screen in place but allows simple removal, screen just slips over peg through small hole.

Lower screen is just there to reduce splashing and noise. Added bonus if algae grows there too but upper screen big enough for size of tank. May double up on upper screen as have plenty of flow!

ThePisces
10-13-2009, 04:29 AM
Hi Kcress, I saw on your design how you had your outlet pipe spraying onto the top of screen. I found that the 1/8th inch slot delivery system as used for a verticle scrubber did not give an even spread of water. The outlet pipe you can see in the photo has a short lenght of 20 mm pipe inserted into elbow joint so I can adjust precisely the way the water hits the screen. I originally had just the 90 degree elbow but the splashing and noise was too great. By adding the length of pipe splashing was cut to near zero and noise vanished. It also spread the water evenly across the entire screen and created a wall of water which backs up against the barrier at top of screen to create a wave like action. No problems with flow at all and very quiet.

Have just replaced the polycarbonate screen that the light unit is sitting on with a 4 mm sheet of glass. This has brought the lights even closer as the original protective screen was a good 1/2 thick. Not much difference and may swap back or source a sheet of thin clear perspex as not keen on loose sheets of glass in there.

The Pisces

ThePisces
10-13-2009, 12:24 PM
[attachment=1:13gpalvc]Tray In Sump.JPG[/attachment:13gpalvc][attachment=0:13gpalvc]Tray With Screen.JPG[/attachment:13gpalvc]

A couple more photos showing more detail of components.

kcress
10-13-2009, 02:05 PM
Thanks for the new pictures. Those pulled-back shots were what I needed. Thanks.


BTW. To reduce your pictures to something that fits better I use a program called "PhotoResize-400.exe"

It's an outstanding program.
Get it here: http://www.rw-designer.com/NT/4.0/PhotoResize400.exe

Here's how you use it.

There is nothing to install. Stick it anywhere you want it.
To resize a jpg just drag it onto the name/icon PhotoResize400.exe

Whatever jpg you drag on to it will be resized to whatever number is in the name - in this case "400".
The resized image will be placed in the same location as the file you dragged on. It will have "-400" appended to the name. It doesn't screw with the original.

If you want the pictures reduced to any other value just change the name to "500" or whatever, (600, 1600, 1234, ? , ?)

If you drag a whole directory onto it every file in the directory will have a size modified copy placed back in it.

SantaMonica
10-13-2009, 08:45 PM
I found that the 1/8th inch slot delivery system as used for a verticle scrubber did not give an even spread of water.

It is self-adjusting; algae grows up into the areas of larger flow, and slows it down.


Tray material ( Polycarbonate) has slight ribbed effect so helps to break up boundary layer

Boundary layer is mostly broken up with faster, thinner, flow. Surges also work, but are another story. Your ribbed material will have zero flow once the algae fills in.

ThePisces
10-14-2009, 01:29 PM
And I quote.

It is possible to get a horizontal working properly, but it takes more skill. ....SM

Un-quote

I could not agree more.

ThePisces
10-14-2009, 02:16 PM
Ok as promised a current situation update. Did tests on parameters to see what they are prior to ATS kicking in.

Nitrite 0
Nitrate 20
Phosphate 3.0...yes 3.0! Have a couple of corals sulking and cleaning glass more often than I want to. This was primary reason for the implimentation of the ATS.
pH 8.4

ATS has been running for approx 48 hours as at 14th Oct 22:00 GMT

Seeded screen with a lovely chunk of turf I found at the top of my weir/overflow. Placed that under upper screen.

Tweaked the lower screen today. I have practically NO water noise and NO splashing. Just strong laminar very even flow across the screens. Flow is if anything too strong.Using a Nujet 1700 litres an hour pump. Can reduce it to 1000 litres per hour

Tray is angled at 15 degrees.

3 x 18w Philips CFT's ( equivilent to 100w each) 300w total at 4-5 inches from screen ( Can move much closer). Light period 18 out of 24.



Removed all filter floss.

Still have good growth of Macro's in DSB area. Expecting them to die off when ATS matures.

UV unit is now removed from cabinet( see photos). I was thinking of running the flow through the UV unit but not switched on. I was going to see if the UV had any affect on the POD population...see where I'm going with that? Desided against it as it reduced my water compression at the outlet.

ChrisD
10-19-2009, 05:33 PM
Well done! You certainly got that up and running quickly - keep us posted on the screen progress.

Don't want to rain on the parade but is polycarbonate sheeting reef safe? I don't have any experience (nor have ever read before now) of it's use. I know that polycarbonate bottles for babies were restricted / banned due to BPA leaching (affects hormones in humans). Don't know if it's in the roof sheeting and would leach and don't know if it would cause problems with the reef if it did. Lot's of 'if's I know but I'd hate not to post and then hear of problems!

Does anyone have any expert knowledge or experience on this?

routestomarket
10-21-2009, 03:28 AM
I used to work in the plastics industry and later healthcare and then just added to my knowledge via google and....

Polycarbonate should be 'Biologically Inert' and due to this is used in medical applications.

I would think, but do not have a full understanding, that it should be fine.

Hope this helps, but google it just to be sure.

Unfortunatley though polycarbonate is sometimes used as a sweeping statement to cover many plastics so it might be worth a trip to B&Q to see what the sticker describes the sheeting as and google that type of plastic for more information.

ThePisces
10-21-2009, 05:13 AM
I think its pretty much safe as it's roofing grade Polycarbonate which is not effected UV light. The stuff I am using is almost as hard as glass.

Latest update and I am amased!!!!

The Nitrate was 20ppm...one week later 5 - 10 ppm !!!!
Phosphate was recorded at 3.0 in my last post..my error. It should have read 0.3> It is now 0.25<
Nitrites 0 no change
Ammonia 0 no change

I seeded the screen with a piece of turf that I found in the weir/overflow. It has more that doubled in size in less than a week and is sprouting out all over!

The rest of the screen is covered in various shades of reddish brown algae with tinges of green.

I am finding that the lower half of the screen which is not so brightly lit is getting more growth on it than the screen which is directly under the lights?

I have absolutely noticed in a short time that my Sarcophyton Elegans which has been very withdrawn for months with little or no polyp extention is looking much more alive and polyp extention is improving. It is very noticeable.

The Critter count in my DSB has exploded!

Water clarity has improved despite the complete removal of ALL fliter media. Water enters the 3ft sump where it is either pumped straigt over the ATS screen or takes a slower route over the DSB area before returning to main tank.

The Calupra in the DSB has exploded too as a result, I expect, of the increased red spectrum lighting?

All this in less than a week and I have not yet achieved a full screen of turf algae just a patch which is now approx 4 x 4 inches on both sides of the screen. Please remember I am only using a single screen on a Horizontal ATS and growth is incredible.

I think I will be able to reduce the 3 x18w CFT's ( 300w total) to 2 and replace one with a 11w? I think I have too much light if anything? The white acrylic lightbox is amplifying the light greatly.

I have also noticed the colouration and activity in the all my fish has improved.

I am only running my Protien Skimmer for the 6 hours when the lights on the ATS are off each day. This will cease all together when I have a full head of steam on the ATS.

Going to clean screen today to remove 50% of brown/red algae. 21st October 13:12 GMT.

To be continued......

ThePisces
10-21-2009, 06:05 AM
[attachment=2:3e1x4ge9]HATS 5.JPG[/attachment:3e1x4ge9][attachment=1:3e1x4ge9]HATS 36.JPG[/attachment:3e1x4ge9][attachment=0:3e1x4ge9]HATS 37.JPG[/attachment:3e1x4ge9]

Photos taken on the 16th and 17th of Oct. Note rapid growth over 1 day! 16th to 17th Oct

ThePisces
10-21-2009, 06:19 AM
[attachment=1:1hik9p2a]DSC00562.JPG[/attachment:1hik9p2a][attachment=0:1hik9p2a]DSC00564.JPG[/attachment:1hik9p2a]

Note massive increase in the patch of turf algae and general overall growth in just 4 days. Compare this to photos taken on 16th and 17th Oct.

routestomarket
10-21-2009, 06:24 AM
Nice results and brilliant test results!

One week in and the difference sounds fantastic!

Not wanting to open old wounds but the horizontals seem to get started so much quicker them verticals as there are many posts from vertical users who see no growth after weeks!

Maybe there is a reason for this that someone can explain?

Well done and happy scrubbing!

ThePisces
10-21-2009, 06:33 AM
Yes funny yo should mention that RTM... Verticles taking longer, well ChrisD had a few issues with the outlet getting blocked on his. Hope you got it sorted anyway Chris?

Yes massive growth and can see the difference overnight. No Blocking of flow and running like clockwork! Results speak for themselves and so early into my project...am impressed to say the least.

ThePisces
10-21-2009, 06:35 AM
Last two photos showing with and without water flow. I'm getting flow on both sides as screen is partly floating on a bed of water.

SantaMonica
10-21-2009, 09:32 AM
I am finding that the lower half of the screen which is not so brightly lit is getting more growth on it than the screen which is directly under the lights?

Possible the bulb is too strong/near the screen, for the amount of flow it has. When flow is weak, the wattage has to be reduced from the recommended amount, or, the bulb distance needs to be increased.


horizontals seem to get started so much quicker them verticals as there are many posts from vertical users who see no growth after weeks

Only if they did the verticals wrong. When done correctly, especially with strong light and a rough screen (like mine) they can be full in 7 days from a brand new screen (like mine was two weeks ago when I converted to a roughed up double layer.) Most of the "delayed" ones you see are because of smooth screens, and weak light. Only last month was it realized how critical a super-rough screen is. I don't criticize theirs too much if they are on a different forum from here, though. Here, however, I do need to point the what is known to be correct.


Yes massive growth and can see the difference overnight.

Yours is indeed having a good start, congrats. And not to sound negative here, just realistic (and experienced). The growth you show is really not massive, it's average. I know it feels great, but remember I've watch hundreds of scrubbers develop from day 1 to one year. When they have rapid flow, strong light, and a rough screen, growth is incredible (i.e., your screen would be 1" thick in GHA by now, and need cleaning). My viewpoint is really not for you, though, so much as it is for readers who are trying to figure out what to build. They just need to know the good and bad to all options.


No Blocking of flow

Because there is no growth yet. When (if) the GHA gets to 1" thick, or even 1/2", that's when flows get stopped. The trick with yours will be to clean before this happens because the algae further down from this will die. I don't think it will get that thick, however, because of the lower flow, and the smaller bulbs that you said you might try.

ThePisces
10-21-2009, 12:48 PM
Hi SM....ok bit confused...when the algae in whatever form grows, to lets for arguments sake say..1inch think. If as you say the 'flow stops' where does the flow go? There is no way that the water on my design can go anywhere other than across the screen/across the existing algae. Please clarify,thanks.

Hey, I do appreciate your comments and views as it only drives me to experiment further. Lesser motals may have buried their heads in the sand with white flags flying.

Onwards and upwards all in the name of happy scrubbing!

The Pisces

SantaMonica
10-21-2009, 02:44 PM
If a patch of 3" algae grows up above the surrounding area, it will re-route water around it, and thus the areas below it will get less. The flatter the horizontal, the more this happens. A steeper angle will help correct this. Another way is to distribute the water up and down the whole screen, using a pipe with holes, instead of dumping it all at the top. A workaround is to just clean more often so that lumps don't get a chance to grow.

kcress
10-22-2009, 12:22 PM
Presently my horizontal is not very steep at all,(~10 degrees), and as SM describes my 3/4" high turf is playing havoc with flow re-routing. I have no sides either :shock:

routestomarket
10-22-2009, 01:05 PM
Kcress, a quick question if I may, I too am at present a fan of the horizontal and have achieved what I set up to do which is no phosphate none of the nitrogen family and abundant pods for fish and corals.

You say you are having problems with the routing of water, but is this having any effect on your nutrient export and happiness of tank?

If you are getting a 3/4" growth in a week and have no detectables surely this is what you set out to achieve?

kcress
10-23-2009, 01:41 PM
Ah route...

I have a very non-comparable tank.

1) It is 165 gallons and it is three 55's chained together with fish jumps. The water is circulated from end to end so it's all homogeneous.

2) It is a very old setup from the age of undergravel filters. The lift for these was achieved by mounting power heads directly onto the lift ports and then burying everything in at least four inches of crushed coral. Most all the pumps have failed so the CC is now acting as a Deep Sand Bed.

3) There is no sump.

4) There now are only two LARGE fish, a cowery the size of a lemon, and about 45 million grounds keepers.

5) There are no regular water changes. It was last 1/3 changed a little over a year ago.

6) Nitrates are sky high. Not 0ppm. Not 1ppm. Not 10ppm. Not 100ppm. But a little over 1,200ppm. It is hard to measure because I have to dilute dilutions to drop the concentration down to where any nitrate kit can actually return a valid reading.

7) The two fish keep the tank they hang in most completely void of ANY hair algae growth.

8) The other two tanks are essentially fallow. There is 7 inch hair algae covering everything but the Tang's specific gardens. The Tang keeps specific garden plots as it prefers only new growth of a certain species of algae.

9) Two of the tanks are essentially fuges.

10) The tanks are dimly lit most of the time but for up to 17 hours a day.

Because of these conditions I have always assumed I would have a dynamite situation for an ATS. What has happened though is that every time I set one up I get only true turf! Very dense, very dark green, macro algae that is somewhat like a putting green in texture. It is tough and tight and sort of like a mini succulent.

Even with high flow and intense lighting it establishes fairly slowly. I have never had a trace of light green hair algae ever appear on my screens.

Knowing that my screens must compete against old well established HA in 110gallons of the 165g tank I don't expect fast results. Though with the nitrate loading I have I would think it shouldn't matter, as my water is like turbocharged plant food. Recently I extracted all the easily extractable HA out of my two refugium tanks. Approximately three gallons or 30lbs of wet but drained HA from my system to give the ATS - more yet - to work with. It didn't seem to make any difference.

So to answer your questions.. I am not having 3/4" of growth a week presently. It is more like 1/10th of an inch a week. My entire screen is not covered but has a peculiar bald spot in the middle that is only now starting to show some additional 'turf' starting on it. It is lit with 90W MH so perhaps the color is not conducive enough. The flow certainly looks good and active in the bald area. However a lot of water is shunting over the edges due to the existing turf and the lack of edges. As for the reduction of nutrients I'd have to say I have seen nothing to demonstrate enough of, nor any reduction, worthy of dragging out the test kit.

Keep in mind my system is a scientific and hydraulic endeavor for me more than an attempt at a spectacular show piece. I get lots of excitement from seeing a new life form emerge and run thru its routines, even bizarre worms and such. So, that's sort of where I'm at in my ATS journey. Learning and experimenting. And since I never have the green HA turf it's hard to compare directly with others.

SantaMonica
10-23-2009, 06:57 PM
with the nitrate loading I have I would think it shouldn't matter, as my water is like turbocharged plant food.

Yes but it's also food for the established HA in the tank. And since that HA has a far greater mass (1000 times more than your screen), it has control over limiting nutrients (probably phosphate). Even when you pulled the HA out, the remaining part was still probably 100 times the mass of the screen; same effect. So since the HA has the market cornered on the current P/N/light/flow combo, only real turf can compete, by using the stronger light (which is where turf excels.)

When any tank full of HA gets a new scrubber, a jump-start period has to go occur; some scrubbers make it and some don't, depending on how much the owner knows. The scrubber must, at least for the jump-start, have very strong light and flow, and a very good screen for attachment to survive the strong flow. After the HA is beaten, things can be brought down to normal. Anthing that works against the HA in the tank can be used to help during this period: manual removal, lawnmowers, reduced flow, or reduced lighting. At some tipping-point, the HA in the tank will really start vanishing, while at the same time the screen will start exploding (with HA).

schnitm
10-23-2009, 08:54 PM
Because of these conditions I have always assumed I would have a dynamite situation for an ATS. What has happened though is that every time I set one up I get only true turf! Very dense, very dark green, macro algae that is somewhat like a putting green in texture. It is tough and tight and sort of like a mini succulent.

[snip]

So to answer your questions.. I am not having 3/4" of growth a week presently. It is more like 1/10th of an inch a week.

I've been there!

Started with nitrates at 500ppm +/-. I had that 1/10 inch of dark gunk for a while. Somewhere around 200ppm I started to get bright green thicker tufts. Below 100ppm the "tufts" were more than 50% of the screen.

At this point there's a discontinuity. I did a 90%+ water change.

Almost immediately the bright green thick stuff took over and what was left of the nitrates went to zero.

kcress
10-23-2009, 10:37 PM
Thanks SantaMonica and schnitm!

The learning process continues.

ThePisces
11-04-2009, 01:47 AM
Ok as promised another update on my Horizontal ATS. Mine has now been running since the 12th October and am very impressed so far with the results.

Nitrite 0
Ammonia 0
Nitrate started out at 20ppm now it's < 5ppm :D
Phosphate 0.3 ... not seen much of a change here with testing but all my soft corals are looking much healthier. Either I have a faulty test kit or the change is down to lowered nitrate levels and an increase in plankton/critters...there's millions of them! When I see a drop in phoshate then I am hoping to see an even greater increase in my corals health.

Fish colouration and general activity is very noticable. My Regal Tangs' belly area is an incredible shade of yellow as is the yellow in my Goldrim Tang...very intense colour change.

I'm using an toothbrush to clean my screen. I brush it very gently from one side to the other in a set pattern so the screen gets cleaned evenly. When I did my first clean and placed the screen back in position I was faced with a slight reddish clouding for a few hours. I rinsed the screen using water straight from the tap...umm I thought. The next cleaning was carried out three days ago but this time I used RO water that was heated in an electric kettle to the same temperature as the tank water.I brushed as before and rinsed in a 5 gallon bucket with the RO water. When I placed the screen back in position and set the pump going again...guess what? NO cloudy water! I'm wondering if the use of chlorinated/ambient temperature water is causing too much shock to the algae which intentionally does not get scrubbed off?

I'll be sticking to my latest method from now on as I am thinking also that over time there would possibly be a build up of chemicles entering the display tank by using tap water? Controlling the pod population I'm thinking will be met by the use of fresh water over salt water...Osmotic Shock.

Comments welcome and also can anyone tell me which parametres they noticed dropping first..ie Nitrates and Phosphates?

Cheers,

The Pisces