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Old 05/04/2011, 10:06 AM   #1251
scott26
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Quote:
Originally Posted by TheFishMan65 View Post

scott26 - you got me thinking. I see a lot of these where people have legs that sit in the sump. Then seem to go through a lot of extra plumbing to run the thing. Could the water just be pumped up a leg (assuming the water is sits in is the water you want to use). Or did I miss something?
I am not sure I understand what you are getting at the water has to run through the piping. Otherwise the PVC would trap air and float around. Also the scrubber will be fed via return pump.

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Nice simple build! Yep the tees will be needed to make your life easier.

Yeah, I am not sure why my local homedepot has them for so cheap, but I am not complaining! Every time I drive buy I buy another few 4 packs! I have enough bulbs to last me a few years now.. lol

How are you planning to do the lights?
I will have two of the 8" lights one on each side I will have to add a mount to the underside of the stand for them to clamp onto though.


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Old 05/04/2011, 10:11 AM   #1252
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You have two legs going down into the sump. At the top of one of them is a T with a hose barb for the incoming water. What If you had designed it as follows:
- Replace the T with an elbow.
= Move the hose barb to one end of the support feet. (Or T off the vertical further down.
Seems like this would mean less flexible piping and might make the alignment easier.


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Old 05/04/2011, 10:12 AM   #1253
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Yes, I can get more of the smaller reflectors (there are 2 large and 2 small). I just thought the larger reflectors would better diffuse the light. Getting the scrubber out isn't terrible either - that whole L-shaped arm comes out via true union to the left. I did think about the design just a little :P


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Old 05/04/2011, 10:24 AM   #1254
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I had to redo it since I had the supply tee at the top if I ever wanted to clean the screen by unscrewing the unions I would have to cut the supply hose off so I moved it below the union so now it is just unscrew and take to the sink.




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Old 05/04/2011, 10:27 AM   #1255
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I have not read through the fifty pages of posts on the subject, so sorry if this has been brought up before. Has anyone tried to build one of the turf scubbers contained in their overflow chamber of a drilled tank? You can set the water level at just about anywhere, and using just the wall of the overflow there is a good bit of area for the algea to grow. You can even make the overflow surge pretty easily, most folk's setup does it by accident anyway. It would just take adding some extra light over this area and some of the mesh material fitted on the interior walls of the chamber.

I have thought about this idea many times but never fully tried it. On my old setup the overflow would surge, filling up and draining down and before long "turf" algea would grow on the smooth plastic walls of the overflow never clogging the overflow though. I would clean a good amount off every couple of weeks. I never added any mesh but figured if I did this would be a basic turf scubber.

If this would work it solves a couple of the challenges that goes with the scubber; space and flow. Also that huge chamber in the corner of the tank becomes good for something. Somebody chime in with the pros and cons of this idea.
I have been designing an algae scrubber that is built-into the overflow box. However the basic principals must still be in place. You need a removable screen, dedicated lighting would have to be mounted to the back of the tank... etc but yes in theory an algae scrubber could be built into an overflow box.


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Old 05/04/2011, 10:43 AM   #1256
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scott - Great idea. Does it also make the area under the tank easier to manage?


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Old 05/04/2011, 10:43 AM   #1257
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Originally Posted by mrpopo View Post
I have not read through the fifty pages of posts on the subject, so sorry if this has been brought up before. Has anyone tried to build one of the turf scubbers contained in their overflow chamber of a drilled tank? You can set the water level at just about anywhere, and using just the wall of the overflow there is a good bit of area for the algea to grow. You can even make the overflow surge pretty easily, most folk's setup does it by accident anyway. It would just take adding some extra light over this area and some of the mesh material fitted on the interior walls of the chamber.

I have thought about this idea many times but never fully tried it. On my old setup the overflow would surge, filling up and draining down and before long "turf" algea would grow on the smooth plastic walls of the overflow never clogging the overflow though. I would clean a good amount off every couple of weeks. I never added any mesh but figured if I did this would be a basic turf scubber.

If this would work it solves a couple of the challenges that goes with the scubber; space and flow. Also that huge chamber in the corner of the tank becomes good for something. Somebody chime in with the pros and cons of this idea.
What? You didn't read all the pages? Man!

As Srusso said, yes it is possible to build one in an overflow. The 'surging' you're talking about it probably because your standpipe wasn't tuned properly, so it was filling up the overflow box and then flushing out. Not really what you want, but it's just a noise factor.

For an overflow scrubber to work, you would have to have the light vertical and strapped to the outside of the overflow, and it would have to be accessible (to change lamps every 3 months) and protected from water splashing during maintenance of the tank and scrubber. The screen would by definition be one-sided, which limits your scrubber size to the width and height of the overflow box.

In theory though, if you didn't have a need or desire for other filtration, you could build one in an overflow box and plug the holes, and just put your return pump in the overflow and go sumpless.


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Old 05/04/2011, 11:20 AM   #1258
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scott - Great idea. Does it also make the area under the tank easier to manage?
Yea it opens up that chamber for cleaning and what not when the screen is removed.


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Old 05/04/2011, 12:02 PM   #1259
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Does anyone have any pics of above tank scrubbers? I currently have mine in the sump, but it has greatly reduced the flow back to the DT. I was thinking of incorporating my current returns directly to a scrubber. The returns are in the overflow boxes that come up from behind the DT. I was planning on using my existing screens.


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Old 05/04/2011, 01:37 PM   #1260
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Update 7 weeks of algae scrubber on a 10 gallon. I posted these photos in my build thread as well, so if you've seen them there as well, I'm sorry.

Before the ATS



7 weeks of running my ATS! Woo Hoo! Nearly completely algae free in the DT. I have purposefully avoided large water changes and purposefully avoided manual pruning to any great extent.








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Old 05/04/2011, 02:35 PM   #1261
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Yes, I can get more of the smaller reflectors (there are 2 large and 2 small). I just thought the larger reflectors would better diffuse the light. Getting the scrubber out isn't terrible either - that whole L-shaped arm comes out via true union to the left. I did think about the design just a little :P
Yeah after I posted that I felt that I could have sounded like I was speaking directly to you... but I more so meant it in respect to all new comers.

Its hard to tell from your pictures how much space you really have to get in for maintenance. I have always disliked clip lights for use with an algae scrubber b/c I always saw myself knocking one off the sump and having an electrified lamp drop into the water... That is the reason I went with the drop lights.

The funny thing is... once you see how well they work... you will never stop reinventing the design in your head


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Old 05/04/2011, 02:40 PM   #1262
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Yea it opens up that chamber for cleaning and what not when the screen is removed.
I love the idea, I just feel like you may create a lot of head pressure with that design. Are you getting good screen coverage? If so, then your fine.


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Old 05/04/2011, 02:46 PM   #1263
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Does anyone have any pics of above tank scrubbers? I currently have mine in the sump, but it has greatly reduced the flow back to the DT. I was thinking of incorporating my current returns directly to a scrubber. The returns are in the overflow boxes that come up from behind the DT. I was planning on using my existing screens.
I drive my ATS from the overflows, and I think is the best design for energy savings and simplicity. Additionally b/c all water entering the sump must first pass through your ATS I think it has better filtering capacity... This is my opinion, I have no way of proving this though.

Above tank designs are nice but they require space on the top of the tank, which at least in an open design means its fighting for real estate for tank lighting. In a closed system, I makes an above design easier to accomplish. Just put it on a shelf above the tank, plumb it and your done.


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Old 05/04/2011, 02:50 PM   #1264
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I get it - it's a great thing you guys are doing maintaining this thread.

Regarding the clip lights; I'm not sure what other's experience with them has been but just from my initial setup the springs seem quite sturdy (though the rear right reflector is hanging upside-down from the return pipe - I wrapped the cord around the pipe to prevent it from falling into the water just in case the clip lets go). Either way, I'm going with a different sump which will necessitate a redesign and I'll address the maintenance angle for sure then. It's been a good experience to set this up once before the tank is cycled though so I have a crack at a redo before things are too far along.

On a side note - I did dose ammonia and bacteria at lunch today so cycle is under way! Gotta build up some food for the algae


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Old 05/04/2011, 05:05 PM   #1265
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I love the idea, I just feel like you may create a lot of head pressure with that design. Are you getting good screen coverage? If so, then your fine.
The return pump that I am using is rated for 1170 gph on my 90 gallon so there is room to use up some gph and the head pressure on my pump is really good as well so no worries there.

Are there any tricks to making sure the water covers the entire screen on intial set up?


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Old 05/04/2011, 06:43 PM   #1266
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I'm about 6 weeks in now, and just in the last 2 weeks I've started to see some really good growth. At first, I took the skimmer and the rowaphos offline, I did put the skimmer back online after 2 weeks. I had a pretty serious outbreak of cyano. Now, there is very little cyano left, I only have to clean the glass about every 4 days. I'm still battling bryopsis in the dt, but I'm pulling whatever I can every couple of days when I suck up any cyano. So far, so good. I harvested about 3/4 cup last week from one side. This week looks like more!


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Old 05/04/2011, 06:59 PM   #1267
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Are there any tricks to making sure the water covers the entire screen on intial set up?
As long as your flow rate is adequate, the flow will even out over the course of the first week. Even a roughed-up new screen is pretty "slick" and the slime that initially builds up will distribute the water more evenly. As you get algae growth, it will even out quickly after a cleaning.


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Old 05/04/2011, 07:05 PM   #1268
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I'm about 6 weeks in now, and just in the last 2 weeks I've started to see some really good growth. At first, I took the skimmer and the rowaphos offline, I did put the skimmer back online after 2 weeks. I had a pretty serious outbreak of cyano. Now, there is very little cyano left, I only have to clean the glass about every 4 days. I'm still battling bryopsis in the dt, but I'm pulling whatever I can every couple of days when I suck up any cyano. So far, so good. I harvested about 3/4 cup last week from one side. This week looks like more!
Cyano is a tough battle. I beat it out in a FOWLR tank that I took over just over a year ago, but it took huge PWCs, sucking out the cyano, running a diatom filter (Magnum 330), adding a skimmer, adding a filter sock, adding a power head, cleaning the pump, running carbon, running Purigen...I think I missed something. Anyways, it's gone now, and has been for about a year! Now I just need to get a scrubber on that tank and knock down the DT algae and nutrients.


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Old 05/04/2011, 11:34 PM   #1269
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The return pump that I am using is rated for 1170 gph on my 90 gallon so there is room to use up some gph and the head pressure on my pump is really good as well so no worries there.

Are there any tricks to making sure the water covers the entire screen on intial set up?
It's all in the slot tube...

I would say plan on cutting three or four of them and chose the best one. Best being straightest, cleanest cuts.


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Old 05/04/2011, 11:45 PM   #1270
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I'm about 6 weeks in now, and just in the last 2 weeks I've started to see some really good growth. At first, I took the skimmer and the rowaphos offline, I did put the skimmer back online after 2 weeks. I had a pretty serious outbreak of cyano. Now, there is very little cyano left, I only have to clean the glass about every 4 days. I'm still battling bryopsis in the dt, but I'm pulling whatever I can every couple of days when I suck up any cyano. So far, so good. I harvested about 3/4 cup last week from one side. This week looks like more!
That's great news! Your ATS will take care of the cyano... It may take some time 3 - 4 months. It's best to allow it to happen slowly and choke it out. Manually remove large patches to speed up the process a little. The fact that your screen harvest is getting close to one cup are signs of your screen reaching maturity.


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Old 05/06/2011, 02:14 PM   #1271
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Thanks for the very informative posts about the use of fluorescent tubes versus CFL. It doesn't look like we have the $0.97 per pack of 4, or even per bulb, at our HDs here in upstate NY.

Noticed through my research that plant growers use sodium and mercury lamps to grow with, but it doesn't look like the wavelength spikes are really in the optimum places...

Was also looking at adding my scrubber on the return line of my 230, since adding it to the drain seems to be potentially unsafe (if it clogs up and reduces flow from the tank). If I add it to the return through a tee, one way to the tank, one way to the scrubber, with valves to control what goes where, then a clog on the scrubber will just build up pressure to the tank and slow the pump down, which isn't a problem! (seems much better than having the pump load up the tank and run dry...) It looks like I have gpm to spare.

Still working my brain around a design...


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Old 05/06/2011, 03:09 PM   #1272
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Was also looking at adding my scrubber on the return line of my 230, since adding it to the drain seems to be potentially unsafe (if it clogs up and reduces flow from the tank).
With a single drain this could be a problem, especially if you have an ATO. Without an ATO it would depend on how much water is available to the pump before it runs dry (probably not a good thing either). If you have more than one drain, its not really a risk.


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Old 05/06/2011, 04:06 PM   #1273
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Thanks for the very informative posts about the use of fluorescent tubes versus CFL. It doesn't look like we have the $0.97 per pack of 4, or even per bulb, at our HDs here in upstate NY.

Noticed through my research that plant growers use sodium and mercury lamps to grow with, but it doesn't look like the wavelength spikes are really in the optimum places...

Was also looking at adding my scrubber on the return line of my 230, since adding it to the drain seems to be potentially unsafe (if it clogs up and reduces flow from the tank). If I add it to the return through a tee, one way to the tank, one way to the scrubber, with valves to control what goes where, then a clog on the scrubber will just build up pressure to the tank and slow the pump down, which isn't a problem! (seems much better than having the pump load up the tank and run dry...) It looks like I have gpm to spare.

Still working my brain around a design...
Use the drain line... its safe. your cleaning the screen every seven days. It will not clog. As we all know water slips through even the smallest of cracks. I have let my screen grow even a week longer then I should have... no clogging... The algae will have to make way for the water as the pressure builds, even then the worst your going to get is a stream of water that shoots off the screen a little, and for that reason people have made simple enclosures to prevent that from becoming an issue.


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Old 05/06/2011, 11:26 PM   #1274
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You have the same risk of a tube clogging as you do when something obstructs a drain completely at any point in any system. A slot tube is a self-controlling device. If algae grows into the slot, the water pressure increases, which prevents further algae growth. This is why it is especially important to make a very straight and even slot, the pressure will be distributed evenly.


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Old 05/07/2011, 05:37 PM   #1275
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Good points! Rather have it in the drain anyways. Guess it's OK for it to go there. Kind of worried about the pump situation, as mine's not really allowed to run dry. Guess that's a problem for any pump though.


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