sand filter

[big tank]

i'm thinking about making or purchasing a sand filter for my 135 gal fresh water tank. can anyone tell me what are the positive & negative in have one on my tank.

[ChicoRaton]

I assume you are talking about a fluidized bed filter. They get mixed reviews. depends on who you talk to. they are great biological filters, but can sometimes dump sand into the tank if the power goes out and comes back on. some are better designed to prevent this. also, during a power outage, the bacterial colonies will die off faster than with some other filters. They're awesome if you have a lot of big, messy fish though.

[Mako]

I've used them, didn't particularly care for them. They work, but are more of a neat gimmick than a real innovation for aquariums. I removed all the sand from mine (a tube-style hang-on tank) and turned it into a CO2 reactor.

For biofiltration, just get a couple BioWheel Pros and good powerheads. If you use live plants (with strong light) skip the biofilter, you already have the best!

[ChicoRaton]

If you use live plants (with strong light) skip the biofilter, you already have the best!

ditto. only mechanically filter the water if you have a heavily planted, high lighting, co2 injected tank. plants love ammonia.

[roliva]

You have to design the fluidized bed filter right to overcome all the problems people talk about as far as sand going into the tank, not restarting etc. I am all for them. Although the bacteria die quickly in a power outage, recovery is quick.