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hobbyist
06-16-2011, 02:55 AM
My 75G has been running for more than a year with an ATS as the only filtration (in addition to live rocks and a DSB). Everything has been working well with only fish and a few mushrooms. The only issue has been a few patches of brown diatom (or maybe cyno) on the sand bed.

Recently I added a few SPS frags and slowly lost them to STN. I thought lack of food was the problem and increased feeding to up to 32 ml of Brightwell Aquatics Reef Snow per day. This did not help with the STN but overpowered the ATS and the brown algae is now all over the sand bed and on some rocks as well. The algae on ATS turned from green to dark and slimy.

Strangely, throughout the whole time NO3 and PO4 have been undetectable using Salifert test kits. Then I found out about the Hanna Phosphorus ULR checker and got one. The PO4 tested out to be 0.07ppm instead.

Now that all frags are lost, I have stopped adding Reef Snow and am confident that the existing ATS will bring things back to the way it was.

While waiting for the existing ATS to work its magic I have decided to improve the design to better handle the feeding necessary to keep SPS.

The new design will have a few improvements over the existing one.

1. Can fit more bulbs while spreading them out over the screens more evenly.
2. More flow.
3. 3D growth.
4. Less bubbles.

Unfortunately due to space limitation T5HO is out of the question. So the design is based on CFLs.

Here is the new design.

[attachment=0:39v1i045]With cover.jpg[/attachment:39v1i045]

[attachment=1:39v1i045]Inside view.jpg[/attachment:39v1i045]

Two single sided screen with usable screen size of 13.5" x 9" each, which is about the same as one double sided screen with 120 square inches.

Lighting is by 5 23W stick CFLs, with a total wattage of 115W. The part on each bulb that actually emits light is about 1.5'' wide and 4" long. The bulbs are spread out as much as possible. The screens are about 3" from bulb surface, which should be far enough to avoid burning the algae.

Flow will be from a Herbie overflow with about 1,000 Gallon/hour. This can be throttle back a bit if it turned out to be too strong.

The side panels of the screen compartment are about 7" high to allow 3D growth and access to the screens without the need to take out the ATS box from the sump. Since the lower halve of the ATS will be in the sump, but above water, if the water level in the compartment goes over 7" it will just flow over the side panels into the sump.

The pipe fitting will be 1", if I end up with enough space to fit reducing bushings I may reduce the pipes to 3/4" after the tee. I read somewhere in the forum that higher pressure in the pipe is better, but I am not sure if this change makes any difference.

Another thing I am not sure is how to size the drains. To allow 3D growth I should have some water above the drain, would a 1" bulkhead allow that to happen or a 3/4" one should be used instead? Should the water drain out as gravity flow or full siphon?

hobbyist
06-16-2011, 02:56 AM
[attachment=1:1xtncwgc]Screen.jpg[/attachment:1xtncwgc]

[attachment=0:1xtncwgc]Lights.jpg[/attachment:1xtncwgc]

hobbyist
06-16-2011, 03:01 AM
[attachment=0:274vfldg]Screen with lights.jpg[/attachment:274vfldg]

Floyd R Turbo
06-16-2011, 06:52 AM
A few comments:

Definitely 1" pipe. The pressure doesn't come from the pipe diameter, but the flow through the pipe.

Definitely 1" bulkheads and drains. You are not likely to get full siphon from the drains in the bottom of the box, but then again, I've never run one that way before. I do know that the one I was running maxed out the flow to the screen so the drain pipe was essentially a full siphon and 2 drains in the box were running with pretty good flow (all 1")

I would consider doing this as a single screen and trying to make it work that way. One double sided screen would be much more efficient than 2 single sided screens of the same size. You mentioned that you wanted access to the screens without having to remove the box. I wonder if this is why you are going down the 2-screen road. Well you're going to have to remove the box when you clean it each week, or at least every other week or so, trust me. You will get algae buildup in the bottom of the box. I ran mine for 3 weeks recently (from 100% clean after tear-down and move, and 1 week with no scrubber running) and the 3D growth at the bottom of the screen adhered to the acrylic and blocked the light to the bottom of the screen. I had always removed the box and cleaned it so this was the first time that had happened, but I've always had to clean algae off the acrylic. So splitting the screen up is not going to make your maintenance easier.

I would go single sided, enclose the lamps on either side and make some DIY reflectors, and maybe down the lamp wattage and go 3 on each side, and add a second drain in the box, or put one in the side up high and put a uniseal bulkhead in it with a small piece of pipe that would let the high-level water drain out against the sump glass. I don't know if that last part made sense, I can probably explain it better.

With a singe 13.5" screen, a 1000 GPH flow will probably max out the flow and your 2nd pipe will be running. You may consider teeing the drain line and putting a valve on the side that doesn't go to the scrubber. so you can tune it.

Just my 2c.

SantaMonica
06-16-2011, 07:21 AM
The original scrubber, for whatever reason (have never seen it), was not keeping up. Thus the brown sand. So yes, adding liquid coral food is going to make it worse. You don't want to feed more until you've got strong green hair growth, and no nuisance algae in the display.

New scrubber: You definitely want 2-sided, so as to avoid dark sides which reduce filtering. I'd do two 23 watt bulbs on each side, with reflectors. Also dry-run it to check for melting.

I think a single 3/4 drain would be fine; I use that size for 800 gph. If you use two drains on the bottom, you won't get 3D. Overflow is not a problem in your case.

hobbyist
06-16-2011, 05:18 PM
Thanks for the inputs.

I will change the design to one double sided screen instead and post the new drawings when ready.

hobbyist
06-21-2011, 02:58 AM
Here is the revised design. A double sided screen with 2 x 23W CFL on each side.

[attachment=2:2lp6gb2j]Full view.jpg[/attachment:2lp6gb2j]

[attachment=1:2lp6gb2j]Inside view.jpg[/attachment:2lp6gb2j]

[attachment=0:2lp6gb2j]Separated view.jpg[/attachment:2lp6gb2j]

Both the screen and the box will be taken out for cleaning weekly. The two light compartment can be moved away a bit for easy removal of the screen box.

The usable screen size is reduced to about 95" (13.5" x 7"), due to single row bulb arrangement. 2 x 23W CFLs on each side gives total light wattage of 92W. Flow is about 500 gallon/hour.

Drain is 3/4". However, just for my own peace of mind, one side of the screen box is slightly lower, so in the case of overflowing water will just flow over that side down to the sump.

For reflectors, either mirror lining the sides and bottom of both light compartments, or individual bulb reflectors DIY from Aluminium beverage cans. Any idea which one would be better? Would the difference be significant?

If the lighting is increased to 3 x 18W or even 3 x 23W on each side, would it increase the performance significantly or at least proportionally?

I am also curious just how much better one double sided screen would out perform two single sided screens. 95 square inch vs 120 square inch, both with about 1W of light per inch, which means a double-sided screen would need to out perform by at least 26% to make the new design better.

Floyd R Turbo
06-21-2011, 04:21 AM
Looks great! I would say you're going to get equal scrubbing power with that vs the 120 sq in double screen. The areas of the screen that get submerged under high-flow (3D growth) will have 2x the scrubbing power, so after cleaning it'll have a bit less power, later in the week it will have more. Also a single screen will get light to the 'roots' better, so algae will hold on to the screen better as there is better light penetration to the deep layers.

I like your idea of separate light boxes. You can move them away if they're too intense, so that's very nice. Any reflector would work better than none, but individual reflectors would probably work a little better. Going to 3x18W would give you a more even spread of light, but you might overpower the screen. Maybe not, I don't know. SM would probably know a little better on that one.

As for the emergency drain idea, that's a good one. I would put the lower side wall opposite of the drain side. You could make teeth like an overflow, or instead of a lower side, just drill a hole about 1/4 of the way down the side, which won't take away from the strength of the box.

also keep in mind that water on one side of the acrylic and heat on the other will cause the box to warp. You will want to reinforce the screen box on the outsides with crossbraces.

SantaMonica
06-21-2011, 05:24 AM
I think making the light box out of all mirrored acrylic would be best. Although, the mirroring won't last forever in salt.

Your wattage will be limited by melting. Overpowering the screen is easily fixed by reduced hours.

A 2-sided screen is at least 100 percent stronger than a 1-sided one, with the same watts.

hobbyist
06-22-2011, 02:12 AM
Thanks Floyd.


I do know that the one I was running maxed out the flow to the screen so the drain pipe was essentially a full siphon and 2 drains in the box were running with pretty good flow (all 1")

How much flow were you using?


I like your idea of separate light boxes. You can move them away if they're too intense, so that's very nice.

Good point. I did not think of it this way but good to know that the option is there.


As for the emergency drain idea, that's a good one. I would put the lower side wall opposite of the drain side.

What is the advantage?

hobbyist
06-22-2011, 02:32 AM
I think making the light box out of all mirrored acrylic would be best. Although, the mirroring won't last forever in salt.

The box will be made of black acrylic. Thin mirrored acrylic is then line the inside of the box. Sounds like it would be better to hold the mirrored acrylic in place using something like cable ties instead of glueing. So that they can be replace when necessary.


Your wattage will be limited by melting. Overpowering the screen is easily fixed by reduced hours.

My current ATS has a similar size light box that is just 1" wider. I have been using 3 x 28W CFLs with no melting issue. I guess the open top really helps vent the heat.

Space is the biggest limitation here so the size of the ATS can not be increased. Instead I want to maximise the performance with more light and flow. If melting is not an issue and overpowering the screen can be controlled by reduced hours, would it be worth while to use 3 x 23W CFLs and increase the flow to maybe 600 Gallon (44 Gallon/inch)?

I remember seeing your reply to another thread (don't remember which though) saying that algae actually does more filtering during the dark hours. In which case wouldn't it be better to have more light to maximise the growth and then reduced hours to maximise filtering?


A 2-sided screen is at least 100 percent stronger than a 1-sided one, with the same watts.

Wow!

SantaMonica
06-22-2011, 03:09 AM
algae actually does more filtering during the dark hours. In which case wouldn't it be better to have more light to maximise the growth and then reduced hours to maximise filtering?

Not more filtering; it just continues the filtering. But the filtering it does at night is based on how much it grows from the light. So you still want to maximize growth.

Floyd R Turbo
06-22-2011, 06:54 PM
How much flow were you using?

780 GPH on a 20" screen, but due to the space, it had to have a double-90 below the tank to go up, then another 90 to go to the scrubber. That is a lot of flow obstruction, so it wasn't perfect.



As for the emergency drain idea, that's a good one. I would put the lower side wall opposite of the drain side.

What is the advantage?

Well, your design sits on top of the trim of the sump, right? If for some reason you have a drain plug up, and the box fills, it is not going to simply spill nicely out of the top of the box. It's going to cascade down the side of your sump and onto the floor. The top edge of the emergency drain slot/hole needs to be below the trim of the sump no matter what.

hobbyist
06-23-2011, 08:26 AM
Another revision.

Light will be 3 x 23W on each side to maximise growth. It can be easily changed to 3 x 18W or even 2 x 23W if necessary.

Flow will be 600GPH and the drain will be 1" instead to cope with the increased flow. The flow can be tuned down if needed. Same with the drain, it would be easier to reduce the pipe down to 3/4" if 1" drain turns out to be too fast for 3D growth.

The side of the screen box for emergency overflow is lowered as well as moved further in. Another side panel about 3/4" away is added to make sure water will only flow down to the sump.

Should the slot for the screen be wider than 1/8" for the higher flow?

[attachment=0:33ivrvb4]Emegency Drain.jpg[/attachment:33ivrvb4]

Floyd R Turbo
06-23-2011, 08:32 AM
I would say start with 1/8" and if you have to widen it, then you can. If you started too wide, you would have to make it again.

hobbyist
07-11-2011, 11:27 PM
Thanks to all the input from SM and Floyd, I have build the ATS to the design and spec shown in the previous posts.

Here are some photos.

[attachment=2:1u8ix4af]Screen and light boxes.jpg[/attachment:1u8ix4af]

[attachment=1:1u8ix4af]Screen box.jpg[/attachment:1u8ix4af]

[attachment=0:1u8ix4af]Light box.jpg[/attachment:1u8ix4af]

hobbyist
07-11-2011, 11:30 PM
[attachment=2:37n7ktvs]Pipe and screen.jpg[/attachment:37n7ktvs]

[attachment=1:37n7ktvs]Light and splash guard.jpg[/attachment:37n7ktvs]

[attachment=0:37n7ktvs]Light and splash guard 2.jpg[/attachment:37n7ktvs]

hobbyist
07-11-2011, 11:51 PM
[attachment=2:2lu4eve1]Cactus rough.jpg[/attachment:2lu4eve1]

[attachment=1:2lu4eve1]ATS in operation.jpg[/attachment:2lu4eve1]

[attachment=0:2lu4eve1]Screen in operation.jpg[/attachment:2lu4eve1]

So far everything is working as planned. The light box got through a 5 hour melting test with no problem. As in the last photo above, there is about 1.5" water pooled at the bottom and hopefully will help with some 3D growth. Even the emergency overflow works. When testing it by blocking the drain completely the water got to within 1/2 inch from the top of the box, but then drained down the side into the sump with no spill at all.

itzrulez
07-12-2011, 03:15 AM
really nice build!
make some photos of everthing in sump! :D
and dont forget to show some result!

Floyd R Turbo
07-12-2011, 06:57 AM
Very nice!

I would still add a cross brace along the top edge of the screen box. It will warp outward right away. You don't need much, about a 1" wide strip of 1/4" acrylic will do, and it wouldn't absolutely have to run the whole length, if you have space between the box and the lamp sockets that will do. You will likely have to take the scrubber offline to do this, because it will have started to warp even after a day of running it, so you'll have to clamp the front and back pieces in place to allow the weld joint for 24 hours to properly cure.

If you don't do it, it won't detract from functionality, but you might eventually get enough warping to cause stress on the vertical joints. That's what happened to mine, and last time I cleaned it I got my hand in there too far and popped the joint open from the top to about 1/2 way down. I ran a bead of weld-on 16 and sealed it up, but it made a mess. But, I need to re-build it anyways after everything I've learned.

SantaMonica
07-12-2011, 01:26 PM
I like the spray guard and the reflector boxes...

RandyAce
07-15-2011, 12:36 AM
is a mirror a good reflector? maybe i will put some to my ats as well.. nice job by the way!

hobbyist
07-19-2011, 07:17 PM
Thanks all for the compliments.


is a mirror a good reflector? maybe i will put some to my ats as well.
Mirror is a good reflector. I think any reflector, mirror or aluminium, would be a worthwhile addition to an ATS.


I would still add a cross brace along the top edge of the screen box.

Added cross brace to avoid warping.

[attachment=2:2c6l2k6o]Brace.jpg[/attachment:2c6l2k6o]

Here is what the growth looks like after 3 days and 6 days. First cleaning was done after 6 days.

[attachment=1:2c6l2k6o]After 3 days.jpg[/attachment:2c6l2k6o]

[attachment=0:2c6l2k6o]After 6 days.jpg[/attachment:2c6l2k6o]

When trying to increase flow the drain noise became quite loud. Any ideas how to deal with it? I could only increase the flow slightly, while still keeping the drain noise acceptable.

Floyd R Turbo
07-19-2011, 07:46 PM
Really nice job!!!!

As for the drain noise, I hear ya. If it's like mine, noise is a function of the vertical drop of the water from the top level in the box to the top level of the sump below, and flow rate. Mine (top of tank, temporary setup tank) had the PVC male/female coupler type drain that was always noisy on the original (sump setup) tank, but on the TOT it was unbearable. I took the PVC out and rigged up a pop bottle to route the water from the hole in the bottom of the box directly to the tank, then eventually rigged up a bubble stop/silencer.

I think there may be some way to help silence the noise by sticking a piece of airline tubing into the drain. I saw this done on a youtube video to silence a noisy open standpipe. Try that, I never did. Leave one end open and stick the other in the drain and see what happens. It provides a smoother source of air or something versus the cavitation of water pulling air into the pipe as it falls.

hobbyist
07-22-2011, 08:24 PM
Found a solution for the drain noise. I reduced the drain from 1" to 3/4", and increased the flow to just enough to create a siphon. This increased the depth of water at the bottom of the screen box slightly, but still less than 2". Just like the herbie overflow, it is now bubble and noise free.


This is what the screen looks like before 2nd cleaning.

[attachment=0:c7zuenfx]5 days after 1st cleaning.jpg[/attachment:c7zuenfx]

hobbyist
08-16-2011, 06:28 AM
Quick update.

[attachment=1:fgyorc7k]3rd cleaning.jpg[/attachment:fgyorc7k]

[attachment=0:fgyorc7k]3rd cleaning 2.jpg[/attachment:fgyorc7k]

hobbyist
08-16-2011, 06:36 AM
[attachment=1:2b5zu57o]4th cleaning.jpg[/attachment:2b5zu57o]

[attachment=0:2b5zu57o]4th cleaning 2.jpg[/attachment:2b5zu57o]

hobbyist
08-16-2011, 06:39 AM
5th cleaning.jpg[/attachment:t8peh0eo]

[attachment=0:t8peh0eo]5th cleaning 2.jpg[/attachment:t8peh0eo]ing 2.jpg

Floyd R Turbo
08-16-2011, 06:55 AM
Great screen progression sequence. I might have to use those pics in my summary.

hobbyist
09-02-2011, 07:39 PM
Floyd, you are welcomed to use them.

Another update.

[attachment=0:3l4dna1t]6th cleaning_no flash.jpg[/attachment:3l4dna1t]

[attachment=1:3l4dna1t]6th cleaning_flash.jpg[/attachment:3l4dna1t]

I have been using my phone camera and has never been able to get the white balance right. The one taken with flash is closer to the real color (at least to my eyes).

At the bottom of the screen (top of the photo, screen is upside down in the photo) are few more long GHA.

hobbyist
09-02-2011, 07:54 PM
[attachment=1:2iz49kpd]7th cleaning.jpg[/attachment:2iz49kpd]

[attachment=0:2iz49kpd]7th cleaning 2.jpg[/attachment:2iz49kpd]

Although the amount of algae harvested has been increasing slightly over the last few cleanings, the progress is slower than I expected, especially the amount of GHA.

May be flow across the screen is not enough, and/or not enough iron?

Floyd R Turbo
09-02-2011, 08:10 PM
That is a perfect example of the growth being best where the intensity is highest. You can totally tell where the lamp is. I don't think I've seen a more definitive picture! It's a good thing that you spaced the lamps so close, or else you would get larger areas of darker growth. Very well designed!

SantaMonica
09-02-2011, 10:45 PM
Just needs more light. Or more time.