Questions about gph.

[Heineken]

What is the rule of thumb for water turnover rate per gallon?? I have a 90 gal tall and I think I need more flow. Thinking about upgrading powerheads. My return pump from the sump is a submersible mag 7. Do I factor this into the equation? Or is it primarily the flow from the powerheads?? I now have 2 powerheads, rated at 270 gph each I think. Everyone seems to have the maxi-jet ph's and I was thinking about upgrading to those.

Just wondering, because I'm cycling my tank now. I'm gonna add some corals 6-8 months down the road. I'm already set as far as adequate lighting, but not sure if I have enough flow. Just trying to be extra careful and cautious! TIA!

 

[malkore]

You want at least 10 x per hour turnover, so 900gph on your tank.

I do think the return for the sump counts towards your total, but things like protein skimmers don't...too low flow and not meant to add current.

Also, you don't have to necessarily wait 6-8months to start adding corals. Your softies like shrooms and polyps can go in once the tank is cycled and chemistry is stable (i.e. as soon as it's safe to add fish, these beginner corals can go in).
When I got started on the salt/reef side, I thought I had to wait a long time...but you don't, if you go with less sensitive species.

 

[loganj]

I agree with malkore and would like to add a couple of things. First, Maxi Jets are the best PH available IMO unless you are willing to fork out the big bucks for a Tunze system. However, I wouldn't upgrade as long as the ones you have are working OK. Your Mag 7 is rated for about 480gph @ 4' head which is probably close to what you actually have when you include fittings and actual pumping height. That puts you just about right for the minimum recommended flow. I would probably add one more powerhead...either a MJ900 or 1200.
Turbulence is more important than flow actually. You want colliding, changing currents in the tank that will more closely simulate the action of waves on the reef. Position your powerheads so that their flow collides and creates swirls in the tank. You might also look into an inexpensive wavemaker such as the "Natural Wave" by Aquarium Systems. Most corals will benefit from currents that cause them to wave back and forth rather than being hammered from one side continuously. JMHO.

 

[Heineken]

WOW. great advice from the both of you! Thanks for the replies. One last thing, what "beginner" corals do you recommend? Any that are really hard and yet look good?

 

[fishfreek]

Describe your lighting setup so we can properly suggest corals for you. Its best to balance the corals with the hobbists lighting setup.

 

[Heineken]

coralife 48" 4x96w 2x10,00k 2xactinic for a 90 gal tank.

 

[fishfreek]

I would say you would be good for softies, mushrooms, Gorgonians, and LPS. If you put SPS at the very top you might be ok with them aswell.

For beginner corals I would say softies like leathers or toadstools and mushrooms, star polyps or button polyps.

 

[theatrus]

I've heard from a few people that a variety of pulsing/pumping xenia is also a possibility for beginner corals. Anyone have any expierience with this?

 

[Heineken]

As always, great adivce on this forum! Thanks!