Hmmm... Just posted but it's gone... Anyway, if this blurb happens twice, sorry.
I have two Fancy Goldfish in a 20 (us) gallon tall with an Eheim 2113 w/prefilter. I plan to upgrade them to a 40 gallon breeder and I want to try a planted tank, but, exactly as Indy6724 suggested, I'm scared to lose the filter. I feel optimistically that, with the plants, I could successfully use the smaller filter on the bigger tank because the plants can assist with the water quality... but that's my comfort-boundary.
Truthfully, is there anything 'natural' about a glass box full of water in your livingroom? My pets have all been of the 4-legged and furry variety until last year when we were suddenly given the Fantail, Swimmer. In a bowl!!! Once Swimmer was in the cycled tank, about 6 months later, we got the Ryukin, Groucho. I've been learning as I go, and now I want to have a planted tank... with my filter! LOL