Return Pump Advice Needed

[sheffboyrd]

I'm putting together a 75g(an All-Glass with megaflow overflow) mixed reef tank and am trying to figure out my return pump. I have a possibly good deal on an Iwaki MD40RLXT, which would give me 1200gph at 4' head pressure. I would like to avoid powerheads in the tank and use loc-lines to distribute the flow from overflow return. My question is, will this be too much flow thru the sump? I only plan to have a skimmer down there and maybe some Live Rock rubble that I have leftover from the tank and some macro algea. Any thoughts or other suggestions for pumps would be greatly appreciated.

 

[Fish_wiz2]

Na it wouldn't be too much for the sump but yes for the overflows. i had a mag 12 (around 1200 too) and my 2 1" holes couldn't keep up so i downgraded to a QO 4000 (around 800 gph), i would do a CL in that case

 

[sheffboyrd]

Really? What is the flow rating for the megaflow overflows?

 

[Fish_wiz2]

Not sure as mine is custom (2 1"), but i recommend to use that pump but just throttle it back with a valve (make sure it is on the OUTPUT and not the input) or run a CL out of it and another small pump for the return. Wiz

 

[sheffboyrd]

Drilling this tank more isn't much of an option for me. So CL is unfortunatly out of the question. Would throttling back the pump damage the pump at all? Wouldn't it be better to T off part of the return line back into the sump to avoid putting undue pressure on the motor?

 

[Fish_wiz2]

i bet not, i have talked with some and you could even close it without damaging the pump just make sure it is on the output and not the input (though i can't really say for your pump as it was stated in general) try asking in the equipment forum. also you can do a CL without drilling, just use PVC on top of your tank (along the rim)-this is what i'm going to do with my new tank. good luck Wiz

 

[Anemone0524]

Megaflow Max rated for 600 gph.

Agree with Fish Wiz....that pump is too much for your overflow.

 

[thegrun]

Reducing the flow from your pump will not cause it any harm as long as the valve is on the discharge side as stated. It will waste a little electricity compared to a pump delivering exactly the right amount of flow, but remember that your flow is going to be reduced anyways by head pressure and fitting flow restriction. It is better in my opinion to have a little more pump than you think you need (within reason), you’d hate to be short on flow and have to get a bigger pump.

 

[sheffboyrd]

Seems like I'll have to find something else. Anybody else here do a closed loop without drilling successfully? Any good threads about this one?

 

[THE ROOK]

If you run a canopy, you can simply go over the back & place the nozzles as needed. Really just need to keep them close to the edge to stay out of the light.

I'm not a closed loop advocate simply because I don't feel the flow patterns are equal to the cost & electricity.

But here's an interesting recent thread.

http://www.reefcentral.com/forums/showthread.php?s=&threadid=1604059

 

[sheffboyrd]

Hmmm...thanks for the link. Although it seems his CL feed lines are drilled and not plumbed over the top. That sure is a lot of different angles to work with in that tank though, haha.

 

[Fizz71]

I did a non-drilled closed loop for years and it did its job ok. I used a simple PVC setup to pull it up and over and returned via flexible hose connected to a Sea Swirl for more random flow. It was fed by velocity pump....T3 I think. Dead silent, good flow, WAY too much heat transfer.

And ROOK is dead on with power consumption. Your Iwaki will run at about 138Watts to get you at MOST 1200gph. Something like a Koralia Magnum 5 will get you 1,650gph at 8Watts!!! It adds up quick!

People tend to see the "deal" they get on the price of the pump but fail to realize how quickly it's not a deal when you check the power consumption of even a few months time.

I know that nobody likes to see powerheads in their tank, but my non-drilled closed loop was just as intrusive, hard to clean (algea and junk on intake strainer), ran HOT and affected my tank temperature. And that's not even counting the 140 Watts it was costing me and running 24/7!

My Velocity still works, and will be used to pump water change water into my tank. 140Watts for a few minutes a month is acceptable. I will have a Koralia Magnum 5 running constantly for mixing the water change water! (I'm building that setup now)

 

[jer77]

Fizz71, you are unfortunately, for sheffboyrd, correct in this case. Powerheads are the most efficient way to create the flow as opposed to a strong power consuming circulation pump. I am however one that likes to have less powerheads and a stronger return flow. In my 75g I used both holes in the RR overflow for the drains in order to allow for more gph. I then plumbed the return over the top without drilling anywhere in the tank. The plus side to this is more circulation, which I feel would have been inadequate if I didn't use both as drains. The problem is as Fizz71 stated, I severly underestimated how powerful of a return pump I needed. I use a Mag9.5 with 4' vertical head and 4' horizontal and 4 openings and 3 elbows and a tee. There is barely any noticeable flow, but I know its much more than it would be if I didn't do this. So I would strongly suggest doing something like this.

 

[sheffboyrd]

jer77 - Do you have any pictures of this setup? The pump I was looking at will pump 1200gph at 4' head pressure, which is quite a bit stronger than a mag9.5. I also worry about plumbing up and over tank sides due to the huge cost in flow. There is little possibilities to minimize the 90degrees and odd angles needed to plumb up and over drastically reducing flow. I think I've settled on putting one or two Koralia PHs in the tank as the best plan.

 

[loosecannon]

I have same set up. I use a mag-7. works nice.

 

[jer77]

Here are some pics of my manifold over the top return on my 75g. Its not as fancy as some, but it gets the job done by spreading out the flow and allowing for more circulation.