Too Much Flow in 120?

GHogg · Mar 2, 2021

I’m currently planning to set up a 120g mixed reef tank. I’m looking at setting up 2 opposing Reef Breeder RP-Ms rated at 2600 rpm.

They will be running one of the programmed settings, so my thought is I should credit them with about 50% at any given moment.

Because of this, I’m thinking I may also put a Hydor Koralia on the back wall rated for some constant flow, potentially 1950-2450 GPH.

My thought process is that the constant flow will provide a very high flow channel ideal for sps between two islands in the tank, while the variable flow from the RP-Ms should provide good LPS flow in the rest of the tank.

Are these assumptions reasonable? Or would 2 RP-Ms on “SPS variable flow” settings be sufficient?

PBar · Mar 2, 2021

Hello,
in my opinion, very unlikely to be too much flow.
Of course it will depend a bit on the aquascape of the tank (and shape).
I suggest you to start with the two pumps and see how it goes... then, after corals starts to grow, you will probably need to increase it.
Hard to say in terms of programming. Depends also if it will be bare bottom or not!

I use 4 x Vortech MP40 in my 100g sps tank (bare bottom)
Good luck!

renzema · Mar 2, 2021

My tank is similar to a 120 but different dimensions. It's SPS dominate with 4 brains and 6 different euphilia colonies.

Running 2 xf350's. One runs 80% constant and the other on a wave setup from 70-100%. These flow 6000gph at 100%. I'm guessing I am around 8,000-10,000gph because of loss when they get dirty and a gyre in a wave program isn't running the peak amount of flow.

You will be fine at your gph and depending on scape and corals may go more. GPH is just a rough number. It's best to setup and see if you have dead spots and work out how to resolve those.