Hi, now i have two smaller filters juwel bio one and pat mini sponge filters. But i just bought fluval 206 for my 20 gallon tank. In fluval i have 3 baskets one came with active carbon so i was thinking to remove that carbon, get all sponges from two other filters and add that to basket at bottom, first basket that will have contact with water, after that bio sponge that i did get with filter, mabey water polisher on top of that and on last basket bio rings. Will that be ok? Will my filter be unstable or it is instantly cicled? Can i introduce new fish in tank or better to wait for week? Btw. Tank and filter media have 3 months now. After 3-4 weeks i would start removing old filter sponges and start adding more bio rings trough next month.