Are trays really required for canister filters.

[ganesan]

I was wondering if trays are really required for any canister filter besides it only separates different media's. Say for example one is using reverse osmosis filter water there would be no metals or other toxins so no need for carbon. Say if you keep only one tray filled with sponge cut to size and a finer sponge or water polisher floss in that same tray and in.the rest of the canister filter space for 3 or 4 trays just keep media like matrix wouldn't the canister filter work well. The reason I posted this is many a time while cleaning the media trays with aquarium water once every 4 months so it becomes sometimes difficult to close the canister because the trays weren't aligned well or there is more medium or host of other things.

 

[Maf 2500]

It depends on the design of the canister. In some (many?) the trays perform a function in directing or channeling the water flow. In more basic designs (such as Eheim Classic) where water enters the bottom and exits the top you can definitely skip trays and just use media by itself (mesh bags would help with mangement).

Is there any filter in particular you are asking about or just a general question?