Flow rates on 240

[Rob Top]

I have finally gotten my 240 up and running, with minimal issues. I am however going to redo the plumbing tomorrow and was wondering about flow rate and turn over times. The system currently has an Iwaki WMD-40RLT which is 765gph and a WMD-30RLXT which is 1025gph. This gives me 1780gph or a little more than 7 turns an hour. This seems like a wicked high amount. There is no live stock yet, just some rock curing so it's hard to see how the curents are going inside and if it really is to much, or just that this is my first BIG tank with high flow rates and I am not use to it.
Any thoughts?

 

[reefNewbie]

I have that same amount of flow in my 90 AGA. It really depends what you plan on keeping in that tank. If your doing SPS or any other high flow rate corals, then that is definetly not enough.

 

[cdeakle]

Good rule of thumb is 10x tank volume an hour. So your in the ballpark at least.

 

[reefNewbie]

how is that in the ball park? im sure those numbers are excluding head pressure, but even if they werent, 240g tank with the 10x rule would be 2400 gph.

 

[Rob Top]

It just seems like so much compared to my 125 gallon. Those numbers I used are with 3ft head pressure, and the pumps are curently at about 5', so it would be less. It will be some time befor it has SPS, but that is the end goal, I think. I have all the lighting, skimmer, Ca reactor, ect, ect to do SPS on this tank, but I waffle back and forth about SPS and fish only. My reef curently is all soft and in a 125. I debate moving the reef to the 240 and having the 125 FO, but the 240 would allow BIGGER fish. On the flip side I think the 240 with a reef would be sweet. I would go on for an hours on pros and cons and I just might on a diferant thread to get some other ideas, but right now i need to tweak some plumbing on the 240.

Would you suggest upgarding the pumps or adding another?

 

[DLS]

I'd upgrade/add a pump. On a 240 you could run an Amp Master 3000 and the two iwakis and I think that'd be a lot closer to good flow than what you've got now. A lot of how much flow you want depends on whether you're going bb or dsb. If you're going with a dsb, then that limits the maximum flow. If you're going bb, then the flow really is basically unlimited. You just have to make sure none of the corals are getting their polyps blown off. :lol:

 

[reefNewbie]

dsb really doesnt have anything to do with it. Just dont point the pumps at the sand and your ok.

 

[sambo1]

The guy I'm modeling my tank after is using a 30-40x turnover rate! Lots of closed loop returns, all of the 1-1/2" size to cut down on velocities. He has a thread on RC. Bstone, I believe, is the author. Really clean looking tank, too.

I'll be using the SEQ 4300 pumps. Two for closed loop and one for sump return. I have a 225 gal with a 40 gal sump, BTW.

 

[Rob Top]

[Lots of closed loop returns]

Are we counting closed loops in turnover rate? I was looking just at overflow to sump flow rates. If we are counting closed loops, wouldn't power heads count too, as all a closed loop does is move water. Right?[/quote]

 

[sambo1]

Everything counts from what I understand. Overflows, closed loops, powerheads, surge systems, etc... I believe turnover rate is meant to be a measure of water movement as opposed to how much is running through your sump/refugium. Correct???

 

[Rob Top]

If it counts everything then I am good, as I have 2 Mag 7 and a ton of power heads. If I am looking for 10x my volume in water movement what is the number to have going through the sump?

 

[sambo1]

Don't know, that's why I keep asking questions and reading. I have 1-1/2" drain bulkheads in each of my overflows(2) and 1" returns. I'm going to flow both drains to my sump and return through 1" sea swirls. So whatever that is in GPM is what I'll flow through my sump.

My two closed loop drains will be 2" bulkheads and 1-1/2" bulkhead returns. Probably four returns on each closed loop. One closed loop I think I will use two actuated valves to flow left to right, and then right to left switching every every few minutes.

 

[scbauer]

Well, if you're worried about too much turnover/flow, consider this...

I have an Iwaki MD 40RLXT. My fish LOVE it. I'm guessing SPS and all other corals will, too, once I get some (fish just moved recently). Anyhow, this pump is used on my 20-Long.

The Iwaki puts out something like 1250 GPH @ 3' of head. I have about 3 or 4 feet of head and a SCWD, so I figure I'm running something over 1000 GPH. That is (with all the estimates) somewhere in the ballpark of a 50 times per hour turnover rate. My water gets circulated through the sump and back just about once per minute!!!

-Scott

P.S. - I've never actually done the calculations for that... thanks for making me do that. I'm proud of my flow

 

[Anonymous]

If it counts everything then I am good, as I have 2 Mag 7 and a ton of power heads. If I am looking for 10x my volume in water movement what is the number to have going through the sump?

Yes, it all counts.

All of your turn-over does not have to go through the sump. You only need enough flow through the sump to make sure your skimmer is addressing the organics.

FWIW, I would get rid of the power heads and, if in doubt about enough flow, add another external pump on a closed loop. A nice set-up for you might be the 40RLT for you main sump return and 2x 30RXLT on closed loops (maybe each feeding a SeaSwirl).

This is similar to the set-up on my 360. I have a Sequence 4600 as my main return pump (with the return being split up 8 ways) and 2x 40RXLT's on closed loops (each feeding a 1" SeaSwirl in the front corners of the tank).