How much flow for 29g SPS build

[Acros]

I am resetting my 29g standard tank and going bare bottom. I would like to upgrade my powerhead. It is a puny 500gph from amazon (would like to move this to the chaeto chamber).

My return pump is a Rio+ 1700. I think I am only getting half the specified flow from this pump. Maybe 300gph.

That leaves me needing a powerhead to provide 1800gph for my SPS dominant build.

28g (filled water volume) * 75 times flow = 2100gph. The return pump provides 300gph.

Is 75 times too much flow in a 29g standard tank? Will my fish be blown away?

Is Hydor Koraile 3rd gen (1950gph) the right pump for me?
https://www.bulkreefsupply.com/koralia-third-generation-1950-pump-hydor.html
Or should I go for a pair of smaller powerheads?
https://www.bulkreefsupply.com/hydor-koralia-evolution-850gph.html

 

[Engrene4]

well i don't have a sps reef but i am getting a pair of power heads that way there is a low chance of dead spots and if you get one strong one it could just blast one coral if it gets big enough and you will get a hotspot and the flow will be restricted

 

[Acros]

I came across these. Should I go for a gyre? Will it be too much?

Jebao CP-90 Cross Flow Pump

 

[Engrene4]

that will do just get another one to combat the dead spot that is created underneath the pumps

 

[Auquanut]

It seems to me that for SPS type coral, you don't have to have an incredible amount of flow. It's more about a random, turbulent flow that is hard to achieve with one powerhead that is running in one direction all of the time.

If you run two slightly lower powered powerheads who's flow patterns intersect at some point, the resulting turbulence should give you a certain amount of variation in flow pattern. Better yet would be to run two powerheads on a wavemaker so that while one is running, the other is off. You'll have to tinker with it to get the flow just right, but that's part of the fun.

Bottom line is that what you'll want to see is movement of the polyps on the SPS, but not too dramatic and not always in the same direction.

 

[HuduVudu]

Flow is far down the list of worries for SPS tanks.

Just my 2 cents.

 

[Acros]

I see, so it’s better to have two pumps like the 2xJebao SW4 or the 2xAI Nero 3 (I know, totally different price category) than just one powerful wavemaker.

I could set them on each ends of the back wall or on the sides facing each other.