36" long SM100 type scrubber?

[scrubby]

SantaMonica, Thanks for all your information, you've convinced me on going with a scrubber for my only filtration. I'm new to the hobby and I'm doing my research prior to setting up a tank. There are a few things I need clarification on, I've reviewed tons of your posts and have noted how the information and recommendations have changed over time as more has been learned about optimizing the ATS system.

I know that some of my questions might be pretty basic but bear with me.

I'm looking at buying a 48x18x24 tank. I want to setup a SM100 type scrubber but I would like to make it 36" long to make sure that it can handle a decent bio-load. I would assume that a 36" screen and pipe would be unfeasible due to the pressure requirements to fill that pipe. I was thinking instead you could have 2 18" pipes and screens. The flow rate to fill 2 18" pipes with their screens would be less than the flow rate for a full 36" pipe and screen correct?

A 36" T5 light is only a small amount more than a 24". If I had to double the full scrubber modules it would be prohibitively expensive for me right now.

Thanks,
Scrubby

[SantaMonica]

Before making it bigger, make sure you have the roughest screen and the strongest wattage T5H0 bulbs possible. A SM100 type scrubber can keep nutrients zero if you feed 10 cubes a day (with no waterchanges or other filters).

If you need more power, a 36" screen is no problem. It does not matter how long the pipe/slot is, if the slot is 1/8" wide for a single canvas layer, and 35 gph per inch. The whole slot will flow. Longer pipes/slots/bulbs are more efficient than shorter ones, but are harder to clean in the sink unless you cut it in half like I do. T5HO bulbs lose 3" on each end; that's 6" out of an 18" bulb.

[scrubby]

Before making it bigger, make sure you have the roughest screen and the strongest wattage T5H0 bulbs possible. A SM100 type scrubber can keep nutrients zero if you feed 10 cubes a day (with no waterchanges or other filters).

If you need more power, a 36" screen is no problem. It does not matter how long the pipe/slot is, if the slot is 1/8" wide for a single canvas layer, and 35 gph per inch. The whole slot will flow. Longer pipes/slots/bulbs are more efficient than shorter ones, but are harder to clean in the sink unless you cut it in half like I do. T5HO bulbs lose 3" on each end; that's 6" out of an 18" bulb.

I see what you mean. I was basing the 36" (SM150?) on your recommendations of 50gal heavy bioload, 90 gal medium bioload for the SM100. I figured why not setup upfront for a heavy bio-load and the best way seemed to simply lengthen your ingenious design. The second I saw your SM100 I instantly realized the potential and the very efficient all around design.

[SantaMonica]

You can increase it as much as you want, but you have to increase the light and flow too. It adds up quick.

[MorganAtlanta]

You'll need over 1000 gph flow for a 36" scrubber. That will be tough on a 90 gallon tank using the overflow, as a standard 1" overflow gives you around 600 gph max. You might want to keep it 24" and make it taller. You'll have to add more light as well. I couldn't find any off the shelf 3-bulb 24" T5 HO fixtures, so you might have to go with 4 bulbs. That would be a huge amount of filtering for a 75-90 gallon tank.