Thanks for all the help earlier with my Eheim canister filter.
I introduced 9 new small fish to the tank yesterday and found 3 of the new fish dead plus another neon tetra from before dead this morning.
Tests look good except the PH was 6.6

I'm wondering if I'm doing something wrong with my filter. Should the output nozzle splash water on the surface or can it be below the waterline? I am curious if that affects the water level. It had been underwater for a couple weeks with no ill effects but now with the die off I wonder. Could that be the result of the output nozzle being underwater?
Is there a right and wrong way to do this? Thanks in advance Drew aka Santiago