Carbon important???

[monsterM]

Hi everyone,

I just wanted to know how important it is to change the carbon replacement cartridges for my hang on power filter. Also, what is the purpose of the carbon. The reason that I ask is that it has been 7 weeks since I started using my filter. I noticed the ph started to decrease from 8.2 to 7.9. Also there has been a slight brown algae bloom over the past few days. I have always had some brown algae which started appearing the second week of my tank set up. It looked like it was going away, but it has started up again. If I change the cartridge will I loose the imponrtant bacteria that got during the cycle? Please help!!!


thanks,
Mo

[Samper]

I'm not the most qualified person at all to answer this but when I started my first tank a few months ago I noticed the same thing......I used a few lbs of live rock a percula and a cherub angel to cycle. The first brown algae I noticed was after about 2 weeks and it sort of exploded. The cherub angel was more than happy to eat the junk and kept it to a minimum. After about a week of that most of it was gone again. A day or two later I noticed another brown explosion this time it went away a little quicker and hasnt come back since. During the first month and a half I did weekly changes of the carbon. Maybe that helps ya. Just so I'll know what equipment are you running on it?