Using the top of the tank

I was wondering how I could find space to build a scrubber and also utilise the existing equipment I have for it.
There isnt really any room in the sump as it is take up with my ATI BM300 skimmer, (I know some of you are a tad anti skimmers but this beast cost me a fortune and is the daddy of skimmers and so it is going nowhere) my Schuran Jetstream calcium reactor and my KM500 kalk stirer and cleartides dual fluidised reactor. There simply isnt room for anything else in there!

So then I looked at the top of my tank, it is a custom built 5 foot bow front tank and on the top there is a large area at the front of the tank that is solid glass with a drain hold cut in to one end. There are 3 x 250watt halides with lumenarcs just above the tank with this area being heavily lit by the lights.

I thought to myself if I pumped water on to one end of this flat area and let it run down to the other area and drain back in to the tank I would have a perfect scrubber area.

I am now looking to find a material that I could cut to size and fit in to this area and then I will get a pump and have a go and see if it works.

Can anyone forsee any problems with this horisontal scrubber idea?
Joe

[attachment=0:2cqhkzjp]scrubber-design.jpg[/attachment:2cqhkzjp]

This is a rough scetch of the idea I have in mind. There is a 6 inch deep lip all around this top section so there is no chance of it overflowing, it will simply drain back in to the tank again...

Any comments?
Joe

What's the tank volume, and the shelf area?

Hi Tank is 60 inches wide by 24 inches front to back by 30 inches deep
and the sump is 36 inches wide wide by 18 imches front to back and the water level sits at about 7 inches deep.

as for the top section I will need to measure it, but there is far more surface area than you would get on a screen in a little bucket or in my sump!
It is 60 inches wide by about 1 inch deep at the narrowest point and in the centre it is about 6 or 7 inches deep.
(obviously the sketch above isnt to scale or even close)

Joe

Ok little update, the water flows far too fiercely over this area and pours over the other brace bars too.
I dont want this so I need to find a less powerful pump to try again, and I also need to find a material to use for the screen as I dont want to scratch up the top of the tank, and I also need to be able to remove the screen for cleaning...

Joe

Ive used a less powerful pump, although it is still too powerful for my liking. However it is now running so I will leave it to run as it is for the time being while I try to find a suitable material for the screen to lay on top of the glass.

Any Suggestions?

Joe

I use plastic canvas that is used for tapestries, got mine from C&H fabrics.
You're in the UK right? If you can't get hold of some I can get it and post it to you if you need?

That is kind of you, however im wondering if it would work laid out flat on
top of glass with a strong current running over it, I need something pretty stiff.

Is it a stiff texture or more flexible?

Joe

it's flexible enough that it can be rolled up, but not so flexible that a strong current would mis-shape it.
I think it'd work well enough, remember, that this sort of setup has been run for several years on a massive scale outdoors to clean rivers and lakes, laid out flat with strong currents flowing over it.
If you can make the current flow as evenly as possible over the whole the screen, then that will help.
The only issue I can see is that you'd do well to raise it off the glass a little so that it doesn't spread too much on to it, otherwise it may make cleaning difficult.

Ok here is my take on this unique attempt. Your tank is about 150g (U.S.). Basic rule would be to have 150 square inches screen, lit on both sides. Your screen area is about 150 square inches, but is lit on only one side. So it's half of what you'd really want.

Second, the effectiveness of halides is still being determined, but based on the two I have seen operate, they seem less effective (probably because they are 14K or higher, and algae wants 6500K or thereabouts.) Growth just really seems less that what even a few 23W CFL's would grow.

Third, your unique placement has never been attempted before. May work or may not, but not being there, I'd have no experience to share about it. There is a chance it would all work great, but there's a very real chance it would not be enough filtering, and at the same time it would be a salt-spray or splash or spill hazard. And at the very least, it would be awefully messy during weekly cleanings.

Based on this, I'm not sure I'd recommend building it. I think a proven low-profile acrylic version (only 6.5" tall) would fit your cabinet, or, would certainly fit on top of the hood.

Did all this make sense? :)

It’s true that your surface area is probably under sized but with the equipment that you have, the scrubber will act as a supplement rather that the primary water purifier. If anything, the skimmer may starve the algae a little bit.

Scrubbers work very well without any surge but many established proponents of turf algae scrubbers feel that you give up around 50% of the efficiency without it. Therefore, if the screen flaps because of the current, then that would be a good thing. You don’t want the algae to get matted. Some of the people on this site find that their vertical designs mitigate this problem with the downward flow of the water but on a flat screen, surge is valuable.

If you don’t have room for that on your scrubber, then it should still work anyway. If you feel like putting up with some of the other potential problems that were mentioned by SantaMonica, then why not try it.

Once you have it for a while, you might find that you love it or that it’s not for you. That is kind of what I did but I loved it and disconnected everything else. I designed a 6” high scrubber that goes on top of the tank. If you find that you like ATS(s), one can be custom made to fit your tank.