So chaps and chappeses, I have this Aqua One Ecostyle 81 tank set up and its filter is a FLUVAL U3 nice, efficient, powerful, silent, and three stage.
But there is one draw back and it is that the filter is mounted just under the surface of the tank to get the best flow and surface agitation for 0xygen exchange, this leaves the lowest part of the filter intakes ( located on the sides of the canister) some 8 inches above the bottom of the tank and accordingly much of the lower part of the tank does not appear to be getting cleaned and detritus is liberally coating the sand.
Fluval don't make one so I was thinking of making a DIY spray bar and connecting it with a piece of hose to the pumps upper outlet, then I can push the pump itself much deeper into the tank in order to get the filter intake as near to the bottom as I can.
Do you chaps think this is Ok has anyone else done anything similar or do you have a viable alternative that does not involve me buying a new pump?
Sounds "do-able" however not many filters actually suck up solid particles of detritus, they deal with tiny floating particles fairly well and the biological filtration of course but most of the filters I use (which tend to be canister filters) do not suck up large-ish particles of dirt.
Usually this dirt is best removed during a water change when you can siphon the gravel.
Bear in mind the purpose of the filter is not to suck up solid particles, but to biologically process the ammonia produced by the fish. As already mentioned, the best way to deal with the dirt is to vacuum it up when doing a water change, and just let the filter do what it was designed to do.