AIO Sump Turnover Rate

[BristolEVO]

Hi all,

What's the general rule for AIO's sump return rate? ie. How many times should the water be turned over?

And is the calculation by day or hour?

I see conflicting things when searching these forums.

My setup is a Fluval Evo 13.5 with appx 11g actual water. Return pump is an AI Axial 40 that is capable of 400gph.

Thanks!

 

[Kingsley_Reef]

2-10 times the tanks capacity by the hour

So if my math is correct your 400gph pump at full power turns over 11 gallons in like 11 minutes

 

[SandNRocks]

Everyones different. I like mine to be closer to 20x. That pump should be fine on the fluval, and could help reduce the need for a powerhead. Im not too familiar with the pump, but im pretty sure you can turn it down with their controller/app too if needed.

 

[BristolEVO]

Everyones different. I like mine to be closer to 20x. That pump should be fine on the fluval, and could help reduce the need for a powerhead. Im not too familiar with the pump, but im pretty sure you can turn it down with their controller/app too if needed.

Thanks! Is the 20x calculated per hour or per day?

 

[KrisReef]

Inflow = outflow, is the general rule of thumb for Aio'S.

Lets talk about it more. Suppose you have a 10 gallon tank with a pool sized back filter, (For sake of discussion, they don't make them this way.)

If your return pump is bring in 100 gallons/hour the tank will turn over 10 times each hour, or once every 6 minutes which is probably a reasonable flow and water exchange rate for corals and fishes.

If the entire pool went one time every hour then no fish or coral are likely going to survive in the display.

In the 100 gph scenario, the water filtration in the pool side of the tank is going to be difficult to measure with that much dilution, while evaporation and pH and alk/CA would be significantly different than the typical tank set up where the sump is a fraction of the DT.

What is helpful is to think about the speed of water moving through the smaller space and figuring out what kind of filtration you want to accomplish in the sump area. Mechanical filtration, particulate settlement, Alk/ Ca balancing, pH will all be impacted by the speed of the water flow through the filter area.

Generally, we want to avoid turbulence but I don't know if there is a rule of thumb for AIO's?

 

[BristolEVO]

Thanks KrisReef, this makes sense. I've been running the Axis 40 at 30-35% which is about 120-140gph. Any higher and the infeed cant keep up and the chambers empty out.

I'm also running an AI Nero 3 at pretty low settings since just the return wont move detritus off the sand by itself. Not while aimed at the surface for agitation anyway.

Just want to make sure I'm not making it hard on my fish or corals. Corals aren't getting whipped around and fish can escape direct flow no problem. So I guess it's fine.