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lokii_37
01/12/2014, 09:52 AM
I upgraded my return pump from an oceanrunner3500 to a ehiem 1262 in an effort to get more turn over thru the sump. the flow I am getting is still pretty low, I am measuring it at about 250GPH coming out of my overflow into my sump. I would really like to be getting about 400-500GPH out of this pump.

The bulkhead on my return is only 3/4", thats how it was when i bought it, and the rest of the plumbing it 1". I am wondering if it will help if I make the, 12"-16" vertical coming from the pump and the 36" horizontal, plumbing to the bulkhead 1.5"? Should I increase the pipe size on both sides of the bulkhead?

dkeller_nc
01/12/2014, 12:20 PM
Does your return have Loc-Line at the end (inside your tank)?

lokii_37
01/12/2014, 12:53 PM
No. it goes from the PVC to a 90 and then to a piece of 1/2" ID tubing. Loc-line is in the plan for getting the most out of my pump/plumbing

dkeller_nc
01/12/2014, 02:29 PM
No. it goes from the PVC to a 90 and then to a piece of 1/2" ID tubing. Loc-line is in the plan for getting the most out of my pump/plumbing

Nope. Loc-Line has a huge amount of pressure drop associated with it. That's why I asked - if the terminus of your return plumbing had a short section of loc-line on it, I was going to tell you to take it off.

We don't have a pic of your plumbing, but I'm betting your flow is getting reduced from too many 90 and 45 fittings in the PVC, and the turbulence of going from a 3/4" outlet fitting to 1" pipe.

As a test, I'd suggest getting some 3/4" vinyl tubing and running it from the outlet barb on your e-heim all the way to the tank (you can just hold the end of it in the tank for the test). Run the pump and observe. This is the most possible flow you can get out of your pump - there are no sharp bends, the size is correct, and the flow is only limited by the height differential between your pump and your tank's water surface.

If that flow suits you, then connect that hose to as few barbed transitions and 90 degree elbows on the way into your tank as possible. Also, remove the foam insert that's in the front cover of the eheim. It doesn't really serve a useful purpose in saltwater tanks. If it doesn't suit you, it's time for a larger pump.

lokii_37
01/12/2014, 03:08 PM
Thanks, this gives me a few things to try and mess around with.

Ill get a picture of my plumbing when I get home from work today. I think currently I only have 2 90s before the bulkhead fitting and one from my stand pipe (correct term?) into the tank. I may just run 3/4" vinyl tubing all the way if this is going to get me the best flow.