Restricting return pump.

[CAreefer]

I am using an Iwaki 35 for a return pump on my 75. All plumbing is 3/4" with no elbows except at the top (Oceanic tank). How far can you/I restrict the return flow without harming the pump. Right now I have the ball valve about 3/4's open. I would like to slow down the return a little. It creates whirlpool effect in my tank. Even with 2 1200's pointing the other direction, purple sea blade gorg. keeps gettin blown over. Pumps seems to run a little hot even at wide open. Any Ideas?

TIA
Marshal

[Starmstr]

Split each input flow into 2 for your size of tank I would use either sea swirls or modular ball tubbing either should work fine without putting to much back presure against the pump.

[Ironreef]

yup put a y on your return end = will reduce alot of flow or spread it out more. a seaswirl would be a better option but the y is the cheap way. This way you can run your pump open and get full use

[tendar]

Starmstr had a good idea by putting a splitter on the end of the 2 return nozels thus cutting flow out of each of the returns in half for flow coming out of each nozel and shile keeping the flow in the tank but disfused more through out the tank. Just go to where you bought your tank and they should have the "Y" you need for around 4-5 bucks or you can get them on line at most places.
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[CAreefer]

I was thinking along those same lines. Leaning towards the sea swirl till I saw the price. ouch. Will opt for the Y for now. Thanks all.

Marshal

[scubadude]

Hi CAreefer

I have a friend who is a professional plumber and he said as long as there is some flow through the pump and you dont do the restricting on the Input side of the pump then you can generally throttle down any pumps up to 75% w/out any harm....just remember to throttle down on the output side. HTH

[CAreefer]

Thanks for the replies, now I don't have to worry about having it run at 50% on the output side.

Thanks again.
Marshal