Turn over flow and powerheads.

[Wolverinegreg]

Okay, so I am currenyly setting up my first decent sized reef tank (220g), but I ould like your help on a technical piece:
I need to get a turn over rate of ideally 6-10 time (more is possible) per hour. Do I take into account the movement created by powerhead in this or not?
For instance, shoud I get a retrun pump from the sump with a minimum of 2200gph + 4 to 6 powerhead (thinking of the Koralia evolution, rated for 750gph) or a less powerfull return pump?
Sorry it is is dumb question, but I am not sure...!

[Palting]

Usually when people say 10X times the DT volume, that includes all your pumps and powerheads. You'll have a hard time getting 2200 gph through overflows, unless you have about 4 of them. Anyway, you'll want most of your flow to be within the tank, flowing over your liverock.

What type overflow and how big a sump do/will you have?

[Wolverinegreg]

I plan to buy a Jebo reef ready with 2 back corner overflows, sump will likely be in a 30g breeder, with another 20g as a refugium

[Neogenocide]

Just to throw this out,

I'm designing my 180g that I'm upgrading to for a max of 2000gph through the overflows. It's going to be powered by a Reeflo barracuda from the basement which is also going to drive my skimmer. I'm hoping it all works as planned, while keeping my electricity bill in check. I plan on breaking out the return to the tank in 2 or 3 outlets using locline so I can aim them where needed.

Scott

[Palting]

Most built-in overflows have a max capacity of 700 gph each. So, yours would be 144oo gph max. Be warned, going max flow makes most overflows really noisy, as in Niagara falls noisy. I wouldn't go more than 600 gpg each for a total flow of 1200. That should give you enough water for the biggest skimmer you can find, as well as feed that refugium. Make up the rest of the flow with your in-tank circ pumps.

[RcToners]

Between my return pump and powerheads I have roughly 7000 GPH in my 150gl display tank with 40 gal sump fuge. Thats about 36x turnover,

[cdeboard]

Typically you want 3-5x running through your sump. So that will be the return. So roughly 1000g would be good. Your overflows will handle that no problem. Then you add in the powerheads to bring the display turnover to 30x or so (depending on what type of corals you want to keep, dead spots, etc). Thats a typical setup.

[cloak]

Here's a good article.

http://www.advancedaquarist.com/issu...3/beginner.htm

[Mavrk]

Originally Posted by cloak

Here's a good article.

http://www.advancedaquarist.com/issu...3/beginner.htm

Yay for this link... I couldn't find it for some reason

Haven't read this in years and it is good to read it as a refresher. Great article.

[aleonn]

Ah, thanks for the link. Had the same questions for my new tank too (180 gallon).

[ruprecht]

Your return pump is responsible for adding good things and removing bad things from your water, e.g., reactors, refugiums, skimmers, etc. In my opinion, this is the true turnover and exchange that should be around 10x for a healthy reef tank. Power heads help remove dead spots in your DT and maximize diffusion across coral water/tissue boundaries. With proper design I can see there being no need for power heads.

Originally Posted by Palting

...You'll have a hard time getting 2200 gph through overflows, unless you have about 4 of them. ...

A single 2" pipe can gravity flow over 3000 gph. It's all a design issue, there are no limitations.