mcahill wrote,
Do you still use the powerheads for airiation ? Or, do you just employ
the power filters ?.............

Not sure what your asking here. RF power heads are used to push the
flow of water down the UGFs lift tube, so the waters flow is then up
through the gravel. This alone will move the waters surface and pick up
oxygen, as would power filters. With both, the surface movement would
be greater, thus more oxygen would be added to the water...
................ Frank