Flow ideas for a 90g

Reef_puck · Oct 23, 2025

What would you use for flow in a 90 G reef? 48x18x24.

not including the mile sump return.

Tank has algae issues right now as well if that makes a difference.

BryanM · Oct 23, 2025

I ran two 2k gyres on my 80g display tank, one at either end, running around 50%.

Rocks reef · Oct 23, 2025

What are you currently using for flow in the tank?
For a four foot tank, you have plenty of options. From a MP-10 on each end, or Jebao, Nero, Tunze, gyre... What corals, if any, are you planning on keeping. Flow really depends on your aquascape and corals. SPS dominate will need higher flow, LPS/softies less flow.

The algae is another issue. What are you parameters at the moment?

Rocks reef · Oct 23, 2025

BryanM said:
I ran two 2k gyres on my 80g display tank, one at either end, running around 50%.

Excellent choice!

Mr. Mojo Rising · Oct 23, 2025

A pair of gyres!

Reef_puck · Oct 23, 2025

Had a MP40 that just broke. And a reef breeders RP-25 along the back.

Rocks reef · Oct 23, 2025

Mr. Mojo Rising said:
A pair of gyres!

I'm leaning that way as well for a 75g tank. It's only 18 wide, those gyres would do great!

Reef_puck · Oct 23, 2025

With the Gyres do they really get clogged fast is the tank has algae issues, and are you referring to the Maxspect Gyres?

Rocks reef · Oct 23, 2025

Reef_puck said:
Had a MP40 that just broke. And a reef breeders RP-25 along the back.

So you are running with just the RP-25 and your return pump?
Do you have many corals?
What are your parameters to try and address the algae issue?

Rocks reef · Oct 23, 2025

Reef_puck said:
With the Gyres do they really get clogged fast is the tank has algae issues, and are you referring to the Maxspect Gyres?

If your concerned about the algae, lets get that figured out too. But, to answer your question. Just like any other powerhead, maintenance is key to longevity.

BryanM · Oct 23, 2025

Reef_puck said:
With the Gyres do they really get clogged fast is the tank has algae issues, and are you referring to the Maxspect Gyres?

Mine are icecap 2ks, but presumably made my maxspec.

1.5 years in, never cleaned, not clogged. Your mileage may vary of course

Reef_puck · Oct 23, 2025

I had another thread working on the algae and corals. The MP40 just broke this week.

So running just Gyre pumps against each other along the top of the tank gets enough flow to the bottom and throughout the rocks?

BryanM · Oct 23, 2025

Reef_puck said:
I had another thread working on the algae and corals. The MP40 just broke this week.

So running just Gyre pumps against each other along the top of the tank gets enough flow to the bottom and throughout the rocks?

Yep.

I do mine a bit different because I like the sides clean.

This is a larger tank, 6 footer, and the gyres are on the back glass on either side of the overflow. I point the flow in to the back glass around 30 degrees and it circulates around the sides and to the front and meets in the middle.

vlangel · Oct 23, 2025

Reef_puck said:
With the Gyres do they really get clogged fast is the tank has algae issues, and are you referring to the Maxspect Gyres?

Yes, mine got clogged even without algae issues. Nothing moves water like a gyre but it was too much tinkering for me. For a cheap option I bought a Carefree Fish wave maker that is dead silent and worked well for a year and a half. It still works well but the controller got fried so now it is frozen on the settings that I had it on. The bigger model is under $90 on Amazon. It's about the size of an mp 10 so low profile. Of course it does have a wire in the tank.

Vortech's are great but pricey. In my 75g which is the same dimensions as yours I have an mp 10 and mp 40 on the right side and the Carefree fish on the left and its plenty of flow for my mixed reef.

Reef_puck · Oct 23, 2025

So you run the gyres verticals and not horizontal. With the offset overflow not sure where I would place these. Where it would not blast corals . Maybe need to remove rock as well.