How much flow is too much flow?
 

Hey,
I am fairly new to marine tanks and i just set up a 30g hex tank. im curious what sort of flow is considered substantial and what amount is considered low? I currently dont have any powerheads, but my return pump from my sump is rated for about 1000l/h (200G/h) at the height difference ive got going now. is that enough circulation for a 30 gallon tank? should i get a powerhead to supplement if i want to keep corals?

What do you plan on keeping? What you decide to keep could help you decide on how much turnover you'd want in your tank.

I've got a 15g right now... (35"x12"x8") and I've got about 50gph coming from the return pump, 240gph from a Koralia nano, and 400gph from a Koralia 1... so total of about 690gph or 46x turnover. I plan on eventually keeping some LPS and a BTA. Currently housing a couple of gobies and a tailspot blenny. Seems like a lot of flow, but the powerheads are quite gentle, so it works for me.

definitely some extremes but this thread gives an idea what others have

Flow is species dependent. On one end you have sea horses and pipefish and the other end SPS. For my mostly LPS 12 gallon nano I have a Maxijet 1200 return pump and a Koralia 1. Every tank will have high and low flow areas so place your animals accordingly.

Yes you should probably have at least one powerhead.

Thanks guys,
Seems im on the low side for this tank.. I do want to keep corals so i'd better go about getting a powerhead i guess.

I have a 33 gallon and I am running 2 koralia 2's, a maxijet 1200 on my skimmer and Aquaclear 50

Works out to around 60x flow :) A lot but no one seems unhappy...

In my 29g I have a 750g/hr, 850g/hr, another very small powerhead. A fluval 450 which puts out at least 250g/hr at its setting, plus the Red Sea Prism Skimmer... So flow isn't a problem for me, or dead spots :)

*cracks fingers and neck*
ahhhh, first "real" post since the return.

Alright, if your tank is anything like I remember hex's to be it's a taller tank, so you'll need to keep that in mind when it comes to things like coral placement, lighting and of course, flow.

What kind of corals you plan on keeping will determine just how much flow you're going to need/want.

For softies/lps you could realistically get away with a larger, powerful powerhead (think Koralia 2 or 3) placed lower in the tank to provide an upward/circular current and your return pump to pick up the slack near the higher parts of the tank. If you're going the SPS route, you'll need more flow, alternating currents and a strong light source...so even though you may be in the early stages of planning this reef out, a final picture is needed so we know what you're shooting for.

Welcome to reefing, may the gods have pity on you ha ha ha

Agree with all that except the SPS/random flow bit. I think that's been hyped a bit much. I might also be saying that because I can't currently afford any sexy controlled powerheads but my sps are very happy.

(first response to your first real comeback post)

i ran a 10G with a vortec mp10 in it plus a K nano and hob filter..