How much flow is enough flow?

Treefer32 · Jul 9, 2021

Aside from lighting, I believe the most expensive part of owning a large aquarium is circulation! The concept is so simple. An under water fan. That's it! Propellers that push water. . . How hard can it be... Yet, it seems so difficult!

In three years time, I've had two MP40s ($450 each), two Corded Skimz S18 ($130 each) powerheads, and 1 Maxspect XF 350 die or malfunction on me!

I've replaced the two older MP40s with Mobius enabled MP40s, meh, not a great improvement. I replaced the Skimz with two Gyre XF 350s, which I have a new motor block coming as a warranty replacement for one of the two.

With the two operational MP40s, if they were ran at max - up to 5,200 gph each. The gyres are rated around 5,000 gph each. That puts me at 20k gph flow at max.

My tank is 70" long, by 3 feet wide, by 31" tall. I have the two gyres mounted next to each other on one end at the surface to create surface tension and flow loops with the two mp 40s pushing back to front.

I am thinking two more gyres on the opposite side so water is pushed either in opposite intermittent frequencies to create a wave like effect. With two Maxspect 280s, that would add another 12k in flow. For a total of up to 32k plus 2k from my return pump for 34k max circulation.

The tank is 350 gallon, with 75 gallon sump. Is 10 X turnover of the display size still the circulation / flow to shoot for?

If it is, I'll have spent $3,000 to get my flow up to speed, and continue to have high maintenance of all the pumps. Just seems like a lot of in tank hardware. I can see why using a closed loop with a return pump would be almost cheaper. . . Is this normal to spend this much on circulation alone?

Or is there a more economical way I'm not aware of?

lapin · Jul 9, 2021

What I have done to cut back on the number of powerheads in the tank ( i only have 4 mp60's) is to use sea swirls on the returns.

Timfish · Jul 9, 2021

Back in the 90s Paletta defined high flow as 10x turnover an hour. Not sure where the idea for such expensive and massive flow rates came from but I've been happy with just basic pumps. 2 Mag 5s with an air pump are my typical pump configuration.

trmiv · Jul 9, 2021

Timfish said:
Back in the 90s Paletta defined high flow as 10x turnover an hour. Not sure where the idea for such expensive and massive flow rates came from but I've been happy with just basic pumps. 2 Mag 5s with an air pump are my typical pump configuration.

Mike uses significantly more flow in his tank today. In this article he discusses his big tank having 120x turnover

Water Flow in a Reef Aquarium: A Comprehensive Guide by Michael S. Paletta | coralvue.com

Author Michael Paletta distills 20 years of reef keeping experience into this comprehensive report on optimal water flow and turnover in a modern reef aquarium.

www.coralvue.com

Treefer32 · Jul 10, 2021

I had a tiny math problem. I wasn't the only one that missed it. Heh. 10x flow of 350 gallon tank would be 3500 gph. 100 times flow * 350 gallon tank would be 35,000 gph. My current aim. To do 120 times flow would be around 42000 gph. A I can't crank one of my MP 40s because 20 inches away it blows my hammers into receding. My anemones recede, etc. So, I've got that MP40 at around 60 %. The other MP40 is fine at 100%. I can't imagine running all these massive flow rates at 100%. Even the two Gyres rated at 5k each, I have to run them at around 80% because that extra 20% really affects the hammers 15" - 20" below them. I know I've lost a couple corals due to lack of flow, so it's a balancing act of getting the powerheads and flows in the right spots. I think another two gyres on the opposite side of the tank will top me of at around 32-35k max flow. It's another$1000 in powerheads.

But, It's hard to beat the area of effect of the gyres.

I'd consider MP60s but I'd need two and they're almost double the two gyres in price. I just don't think the Mobius functionality compared to the gyre circulation methods is really all that important. I was so frustrated with the app I just used the controllers attached to the MP40s to set them to a constant speed. I had spent an hour configuring a custom program on the Mobius app, and I'm not sure what happened, I don't know if they reset when they lose connection with the app, or what actually happened, but all programming was lost. So, I just said screw it, it's not worth my time to figure out, I just set them to constant speed. The MP40s were so much better when they could be controlled by the apex, which I can control through my phone if I want. .

I'll be buying the Hydros Wave Engine from Coral view to connect all 4 Gyres to, and configure with a computer or phone. I hope the controller works better than the Mobius app.