what is the ideal Flow?

jwilkey2468 · Jan 13, 2022

I am in the process of setting up my 40 gallon breeder and have an aio fiji cube filter mounted to the back center of the tank. I believe it pumps around 400 GPH and I have 2 power heads pumping 530 GPH. I am aware of why aquariums need flow, I am just curious if anyone has any tips for finding appropriate flow and or how I should set my system up. Currently I have my filter outlet pointing at the water surface to introduce oxygen to the system, my left power head is pointing at my rock hitting the back of my reef rock and my right one is pointing in-front of my reef rock hitting the front of my rock.

mattdg · Jan 13, 2022

It sounds like a good amount of turnover to start with. The throughput of your AIO is totally fine. If that were a sump, you'd be cycling 10x, which is PLENTY. You are likely going to need to add flow as you add coral and discover where the dead spots are in your tank. Looks like there may be a few places where that will be the case. Other than that, it is far better to start with too little flow and see how your coral eventually react, adjusting accordingly. LPS / Leathers, you may be fine. SPS, you will definitely need a lot more turnover. Maybe eventually consider one of the smaller Red Sea Gyre's. IMO, they are the best bang for the buck, easy to clean and will maintain the oxygen levels / surface agitation, freeing up one of your prop pumps to place strategically.

FiddlersReef · Jan 26, 2022

I’m not sure where I ran across this, but extrapolating from this worked well for me.

Example is a 100 gallon display with two MP 40s for easy math:

Target 20-40x tank volume flow rate per hour, divided amongst all pumps.

Display volume is 100 gallons, so that’s 2000 to 4000 gph. (100 x 20 to 100 x 40)

Both MP40s peak at 5000 gph. So they are set to 30% reef crest, which is 1500 each. (5000 x 30% = 1500)

That means combined they peak right in the middle at 3000 total gph.

Then adjust to taste.