Pump opinions please

I hope to be sending for my pump tomorrow . I,m looking at a mag 950 but don,t know if I should bump it up to a 12 . Do you think the 950 will be enough ? The tank is predrilled and the overflow is rated for 700gph, and with about a 4ft head on the mag950 it should give around 800gph, so the math seems like the 950 would be right , I just would like some other veiws before I buy.
Thanks in advance

 

I would go with the mag7 for the 55g and the mag9 for the 90g

 

If your overflow is rated at 700gph max then if you go with the Mag 9 and you figure you have 4' head pressure and 800gph then your pump will pump the sump dry because the overflow cannot keep up with the pump!

You want the flow through the overflow to be higher than the flow of the return pump once head pressure is accounted for. Just remember that every 90 degree bend in the return line counts as 1 foot head pressure.

If you want to use the mag 9 then you may need a flow control valve to dial down the flow.

I use a Quiet ONE 3000 as a return pump for my 800gph overflow. You could also use the Quiet One 4000 (low pressure 4000 as opposed to the 4000HP)
I se the Quiet One's because they are very quiet compared to other pumps, but the Mag pumps are great pumps!

 

I think MAG 9 is perfect. Just put a ball valve after the pump and then you will have some room to play.

J

 

so much math! lol

 

Wow every elbow counts as 1ft huh. I was thinking of pipeing around the top of the tank and putting lock line in each corner to aim the flow. that will add 6ft to the head pressure for a total of 10ft of head. Should I still stay with the 950 or go bigger and T it for control?

 

If you have 10' HP then go with the bigger pump, otherwise stay with the Mag 9 and you'll be ok. I use 1" pipe from the pump to the tank, the switch to 3/4" lockline and make a gentle curve to bend over the top of the tank so I dont have 2x90 degree bends. I'm not sure if this helps with decreasing the HP or not.

I tend to not to use bigger pumps then I need because of power consumption and noise.

 

Well I went with the mag 12. According to the charts with 10ft. of head the pump should deliver 600gph, which is 100gph under what the overflow is rated.
Thank you and Karma for your help