Hum, I did take my FX6 apart yesterday. Not much dirt or dust had been trapped. I have some 20 .and 30ppi foam and some synth glass pads. The synth glass did catch more than the foam but still not a lot. I cut up an old T shirt and put a few layers of that between the layers of synth glass. Not much change over night so that does not seem like a good idea. I am now 2.5 days of filtering time and the tank is still cloudy??
I was going to start my cycle by adding some ammonia but was going to wait until the tank cleared. I wait another day or two I guess.
Meanwhile, I am working on a auto top off system. I added the fittings under the kitchen sink, (Tee, reducer to 6mm, pressure reducer, elec valve, elec valve, 6mm plastic to tank) I found two really cool micro float switches and mounted them in a 1/2" glass tube to place in the tank. A 24vdc power adapter, two small relays, and I'm done. It works at the sink and I'll get that installed later today maybe.
Initial Par reading in the new tank are encouraging. Even with the silt or dust in my water I can get high in the medium light range with the new LEDs. Idea is to adjust the light to 75% of the low range so I have plenty of light.