Before any drama starts, i would like to apologise for any offense to anyone below, but i really tried to phrase it in the politest and nicest way i can to someone who tried to justify a bad advice.
I would like to advise you on holding on to any more of your advices and fact check them online first.. as what you said here could have caused OP or some newbie that found this thread in google to spend money on something that is not even remotely necessary.
Okay, First and foremost, filter media function is not to catch debris they are used to house bacteria to convert ammonia to less toxic forms, nitrite and nitrate.. thats why there's mechanical filtration, filter sponges(like those on sponge filters) or filter wool to filter debris you speak of, And if you didn't know.. any ph under 7 will convert ammonia(un-ionised ammonia) into ammonium(ionised ammonia) which is alot less toxic(think along 100x) than ammonia because ammonium cannot pass thru cell membrane while ammonia can.. and what water do channas prefer and should be kept in? Answer is soft and acidic.. which is under ph7. So ammonia is converted to ammonium which shows up on test kits as ammonia cause they have the same base chemistry... so saying channa need media filtration is wrong. Having media is good but definitely not a need.
Secondly, channas do not need nor prefer "good circulation" they prefer slow moving or stagnant waters(please go look at their wild habitat).. good circulation in water is the exact opposite of slow moving stagnant waters.. If you do "good circulation" to your fire and ice that's fine because it's your fish and you do what you think is best. But please do not give the wrong advice to someone else because it is widely known that channa prefers slow or stagnant waters.