I have a 29 gallon tank that's been up and running about 6 months with no issues. I have about 15 lbs. Live rock, 20 lbs live sand, 2 clowns, 1 royal gramma, 1 neon goby and some snails and hermits. I currently have a hob filter with chemi-pure elite as the main filter media. Everything is doing OK but I want to upgrade to an external canister. What problems, if any, should I be concerned with if I switch?

