when I do that JM, won't the pump suck more water out of the canister as less of it will be coming in, therefore causing the pump to run dry eventually?
I am not questioning your expertise but just trying to understand how that filter works better.
Do not close the intake/suction line going into the canister or you will 'starve' the pump. Play with the output/pressure line valves to adjust your flow. Play with the spray bar angle until you get the water movement flowing across your tank the way you want it. It can keep the debris and poop moving until your filter can pick it up.
It has been my experience that your filter will reach an equilibrium, and not "starve". That's my experience with my Mag 350. I have an Eheim 2026 that the flow adjustment closes both in and out tubes, so that is something to consider, since I think your filter is supposed to be loosely based on the Eheim 2026.
the flow adjustments on the tubes are independent from each other, but I did read somewhere that my filter is similar to the eheim.
when I first set it up I tried closing the in-flow valve and the pump sucked some of the water out and now the water level in the canister is lower than originally. I have the IN valve open wide now and reduced the OUT flow a little bit. filter seems to be working OK and is very quiet.
thank you all for your input, I realy appreciate it.