top off on a nano

[blaster]

Just hooked up a aquamedic doser sp3000 for a top off,but its not strong enough to get water from the floor to the tank.

[Chase31]

put the water on a stool or table or something, maybe have it top off into your sump ( not sure if thats possible)

[Rippin]

I've used the SP3000 with success on my 14 gallon nano. I mounted the pump mid way between the fresh water reservoir (bottom of stand) and the tank. My stand is about 28" and the tank is about 14" high.
Are you sure you didn't install the backflow valve backwards?

[blaster]

i got the pump used,but he hadnt used it so i dont know what the backflow valve looks like

[Rippin]

Here's a link to the instruction sheet:
http://www.aqua-medic.com/products/docs/Dosing_Pump_SP_3000.pdf

The check valve is blue and looks like any other in-line check valve that you can get at a fish store. If you don't have it already installed in-line between the pump and the tank then you probably don't have one; therefore the valve installation is not the problem. Does the pump work if the head height is reduced?

If the pump hose (white one) is not properly greased it will not work properly. Grease should have been included in the box when originally purchased. Any thick silicone grease without any petroleum distillates or solvents will do the job.