Just some background,  I had a 55 gallon glass hexagon for about 7 years that developed a leak in the seam so my wife and I decided take the big plunge and transfer our fish to a 20 gallon temporary tank until the 120 gallon Tenecor we ordered was ready.  That was 2 months ago and now the new tank is up and running and there are 7 Tiger Barbs in there to do the cycling while the bigger fish wait their turn to get in.

I'm using a standard wet-dry filter.  About how often do these need to be cleaned?  I know the bioballs never have to be cleaned but I'm assuming the filter material above should last about a month or so?

After the tank has been cycled, is it advisable to put carbon filtration in the filter?

What kind of chemicals/vitamins should I stay away from to avoid yellowing or discoloring the tank?

What kind of auto feeder can I use in this tank?  It has a removable insert in the top of the acrylic.  Most seem to be the type to hang on the back of a tank.

The prefilter overflow sounded like a toilet constantly flushing, I filled the prefilter with bioballs and put filter material at the top to filter out any food particles to act as a silencer.  Is this OK? Can anyone recommend another, maybe better, way of silencing the pre filter?

Thanks for your help, I'm sure I'll have more questions!

Ed

120 Gallon Tenecor 24x24x48