Can there be TOO much water movement?

[Palting]

When I set up my current 110 gal, a quick research told me I should use a Koralia Evolution 1400, so I bought one. I set it up to the right of the back wall and pointed it left diagonally across my 18" width tank. That thing appeared to be blasting wa-ay too much. All my fish, including my strong swimming tangs would avoid both the direct and rebound path of the generated current. So I replaced it with two 750's and put those on the side walls. Tangs seem happier.

Anyways, my soonn to be new tank is a 125 gal, 72x18x22, with corner-flows in each back corner, returns driven by 2 Maxi-Jet 5500's pumping out about 900 gph at a 5 ft head, each return with two spouts. So, that's a total of 4 spouts, each spout pumping out maybe 450 gph. I plan to have one spout from each back corner aimed at the front middle of the tank, and the other spouts probably aimed midway between the middle and their respective adjacent front corner. I am thinking this will keep each front corners available for the lower flow lower light prefering corals.

My concept is that the back middle of the tank will be built up for the strong light loving corals, which usually love strong flow as well, right? So now I have this 72" span. I was thinking of putting those Koralia 750 at each front corner and point them both towards the mid-back. I'm unsure the 750's can generate the needed flow for the "strong flow" corals, but am a little wary about too high flow that will blow the fish around. Should I get another pair of Koralia 750's, place then mid back, and point them back at the front corners?

Sorry about the long post, but I wanted to make sure y'all got the right picture and my concerns.

Thanks in advance !!!!!

 

[ruprecht]

Can there be TOO much water movement?

Depends entirely on the types of corals you intend to keep and where you ultimately decide to place them.

 

[keto]

I run two 1400 S and a mag 18 with 4 discharges

 

[Palting]

That's a big pump and a lot of flow, keto. How are your swimming livestock taking it?

 

[stevek480]

In my 125g I have a Koralia magnum 5 (1650gph) & 6 (2200gph) with an eheim 1262 return. The fish seem to love swimming into the current, and my clownfish also enjoys getting taken by the current straight across the tank. I think you really need to be more concerned with your corals and the flow rate rather than the fish.

 

[mutateddogbone]

I have a Mag 9.5 return pump, 2 koralia 4's, 1 koralia 3, and a seio 850 on a 75g tank. my SPS love it and my LPS dont seem to mind either, but i dont really have any softies other than GSP and Pom Pom xenia in low flow areas in the corners

 

[keto]

they love it !!

 

[Palting]

OK, OK, the noob gets it . I am way too under-flowed. Thaanks for setting me straight.

If I want to keep high flow loving corals eventually, I probably need something like a Koralia magnum 5 or 6 on each end of the 6 foot tank, leave some space in the corners for lower flow loving corals, and let the fish fend for themselves. Is that about right, guys?

 

[j.p. harrington]

heck in my 75 i have 1 evo 1200 1 evo 1400 2 nanos and 1 maxijet 1200 and thinking i need more

 

[mutateddogbone]

in the wild, fish get blown around much more than we can recreate in our tanks. a good number to start out with is 50x turnover rate per hour, return pump gph + powerheads gph = turnover rate

 

[Palting]

Ok. What now, guys? Are two koralia magnum 5 or 6 at each front corner enough to help me keep all options open for coral? Do I need more, or stronger? I want to get it right the first time I set it up, and since it seems I need to buy new circ pumps anyway, might as well buy the right ones.

Thanks!

 

[yongpanda]

In my opinion, I think to the importance of flow rate, It had to do with a varied stream of flow also. A giant pump in a tank isn't as ideal as 2 or 3 pumps supplying the same turnover rate.

 

[riiz]

Or go with a trio of Koralia 4s, maybe 2 situated more near one side and another at the opposite for a nice mix of flow rates and turbulence.

 

[Aquarist007]

OK, OK, the noob gets it . I am way too under-flowed. Thaanks for setting me straight.

If I want to keep high flow loving corals eventually, I probably need something like a Koralia magnum 5 or 6 on each end of the 6 foot tank, leave some space in the corners for lower flow loving corals, and let the fish fend for themselves. Is that about right, guys?

Usually the corals that like lots of light also like lots of flow for eg sps corals.
I would keep the flow high at the top of the tank and then lessen it as you go down to the bottom where corals like mushrooms don;t like a lot of flow and can do without a lot of light

The surface of your tank should be really agitated==that is the site of gas exchange for your tank.
If you have too much flow then try to mount the koralias low in the tank and point them upwards. This won't kick up the tank and will supply lots of flow to the top area of the tank

Ideally you should arrange your power heads so the flow goes downward from the returns, across the substrate, up to the top of the tank and then over to the drains.
The most flow should point towards the overflows.

 

[Palting]

Thanks again, all. And thanks for the tips on flow directions, Cap'n. I think I've got a fair idea now on where and what to put and where to aim.