What size return pump???

[abushr]

Hi everyone,

My friend has a 40gal. tank. She currently is running a canister filter, but she just bought a used sump with backpack overflow. Our question is....what size of pump do we need to push the water back up into the tank for adequate water flow? Would a mag2 be enough, or should she go mag5?

Thanks for the help.

 

[thatguy559]

what is the flow rate for the overflow? if its 600gph then i would go with a mag7 or mag9

 

[bigblue141]

Look for a return pump that does 5x your DT volume.

Calculate head height and get a pump that will do 2-300 GPH.

 

[TotalVapor]

If she has an in sump skimmer then her return pump should be 3X the rating of her skimmer. A return pump should not be used for flow inside a tank.

 

[roblou]

I would also suggest that when setting up the sump & return pump that she puts a ball valve between the return pump and the display. By doing this, she will be able to throttle the flow down if needed (some return pumps have built in flow control valve, so in that case a separate valve may not been necessary).

HTH,

Rob

 

[jrgilles]

I would also suggest that when setting up the sump & return pump that she puts a ball valve between the return pump and the display. By doing this, she will be able to throttle the flow down if needed (some return pumps have built in flow control valve, so in that case a separate valve may not been necessary).

HTH,

Rob

Putting in a ball valve like this to throttle down the pump can put unnecessary strain on the pump and shorten its lifespan.

A better way to throttle down the pump is to "tee" off of the return line, and have it return back to the pump, then put in a ball valve on this extra piece of pipe. If this valve is closed, all the water will go back to the tank, and as you open it, you will get more and more water doing a closed loop to the sump with less getting to the tank. This allows you to decrease flow back to the tank without building up unnecessary pressure on the pump.

Putting an inline ball valve without a Tee just just increases the head pressure on the pump more and more as you close the valve until there is so much pressure the pump can't push water through. This is very bad on pumps.

Here is a bad drawing in found in my photobucket account that shows what I'm talking about. This isn't the final design of my plumbing, but you can see how I did the return line, as it is how it was actually plumbed in. In my plumbing, I added a "+" instead of a "Tee", with the extra leg going to a flexable drainline that I can turn on and off with a ball valve. I use this drain line for water changes, and it makes them really easy. Can dump 16 gallons of water out of the tank in maybe a minute or so.

http://i235.photobucket.com/albums/ee320/bobgoulsby/plumb2.jpg

rob

 

[abushr]

Thanks for all the information. I really like that flex hose idea.

Have a great day everyone!!!

 

[jrgilles]

I also have a short pice of flex tubing. Between the return pomp and the "+" connector so the vibrations of the return pump doesn't vibrate all the plumbing. Having the drain line for water changes using the return pump makes my tank chores a lot easier, I highly recommend. Good luck