Most importantly, post water parameters. Measure before a water change so we see it at its worst. At least nitrates and phosphates.
I've made a canister filter work, but for a while it was pushing nitrates up around 20. I used to just rinse the loose crud out of the foam filters with water change water (weekly). Now I do it more aggressively with tap water, much cleaner and 0 nitrates. All I have in the canister is foam filters and the ceramic bio media.
The tank is still young, growing pains, you'll pull through!!
Trust no one - The ich is out there.