Enough filtering?

[parkedcar]

On my 125 i have 2 ac500's and an XP3
I just picked up a full 90 gallon set up, full 20 and 5 and a crap load of extras for $100. Origional intensions where to take what i need and sell the rest. But my father is taking the 90, but using his filter, and i am trading him my 55g set up for his 75. But the 75 will have no filter. I took the magnum 350 pro that came with the set-up. I like it because its a pollishing filter, and i always feel my tanks could be clearer. So i was thinking of putting the xp3 on the 75, and the magnum on the 125 with the AC500's, since that is my display tank in my office.
If i do this, could i take one of the AC500's and load it with all biomedia? Will this be any benefit, or would the lack of oxygen in the filter keep the bacteria form thriving?

 

[cougar579]

Why are you loading the AC with bio-media? Doesn't it already have bio-media? I thought you were keeping the AC's on the 125. To answer your question about putting the magnum on the 125, yes that will be fine. You will be jump starting your 75 tank with the XP3. I also suggest you do a gravel vac on the 125 into a 5 gallon bucket. Dump the dirty water in the 75 to help start with the cycle of the new water. You could also do a 50% water change on the 125 and add it right to the 75. What ever floats your boat.

 

[parkedcar]

I just figured get rid of the carbon in that filter, use a small prefilter at the bottom, and just fill it with bioballs, right now i just have the small bag ontop of the carbon. and a AC sponge. i thought maybe that having the 1 AC loaded with biomedia might help with the biological filtration.