Sump Pump

[Betta5]

there are these pumps in all different lph (which do you suggest?)
http/cgi.ebay.co.uk/5000-LTR-INLINE-IMME...7QQcmdZViewItem

My tank will be 4'x18"x12" (LxHxW)

and the sump is (24"x12x12)

max 2-3' under the tank it would be?

Thanks

 

[andywg]

They look fairly good.

I would advise against trying to get too much turnover through the sump as you are wasting energy fighting gravity. Far better (and more economical) to have a sedantry 5x flow through the sump with the main circulation in the tank.

 

[Matthew5664]

however do rember that if you have the skimmer in the sump you can only skim at the return pump rate even if your skimmer pump is more powerful.

 

[AK77]

If memory serves me correct, Melev's website recommends a flow rate of 3-5 times that of the display tank. If my math is right, your tank will be 170 litres (121 x 46 x 30). A 5000 litre pump will be major overkill IMO. Pumping the water up 2-3ft from the sump will reduce the flow rate will to about 4000 LPH. This means that you will need an overflow system capable of handling at least that much, otherwise you will flood your room as the sump empties faster than it can be filled. How are you draining the the tank to the sump? Durso? Calfo? Overflow box? The only other option would be to install a ball valve on the return pipe to reduce the pressure and flowrate.

Personally though, I'd save myself all the headache and remove all risk and go for the 1750 LPH version from the same vendor and install a drainage system to match. I was bidding on one earlier for my 180 Litre tank, but some git outbid me at the last minute