[Birdman]

With the deep substrate used for plant aquariums I don't see under gravel filters being used. Are these bad? if you have an inch or two of substrate won't it go an-arobic?

 

[fshfanatic]

I would be more worried about the root systems entangling in the plates.

 

[mistergreen]

we don't use undergravel filters here
They're unnecessary and are messy sometimes.. I've had you blow mulm up from the substrate into the water.

Most people here don't use any heavy organic substrate so the chances of anarobic spots are rare. And plant roots and trumpet snails help aerate the substrate.