So. I am new at this and ended up in the shrimp hobby organically and not completely by intention. BUT that is a long story. I like and am attached to them now. I now know what I need to do for a shrimp specific tank, when I have money for my birthday... for now, I have a 3.5 gallon tank that came with it’s on carbon filtration system. My shrimp are doing well. The tank is cycled... 0 ppm ammonia, 0ppm nitrites and Nitrates range from 0-10. The increase in nitrates from 5-10 occurred this week. In any case, I do weekly 10% water changes. I know they say not to run a carbon filter longer than a month. This one has been running for 2 months, and I have rinsed it in aquarium water when doing water changes at least twice...in the bucket of course. I don’t have the equipment to do anything complicated... when and how do I replace the filter w/o losing my bacteria or cycle. Thanks for your time and assistance.