plans moving forward for the plunge-and question about a stunted comet's future

My 75 gallon tank is empty and I'm in the process of giving it a good cleaning. I've ordered tiles to make a mosaic for this tank, so it will be several weeks before I'm ready to fill it again. I've lost my bio filter, but will put extra bio-stars in the Rena filter on the 20 gallon to seed the big tank when the new fish arrive. I'll trade out one of the sponges out of the running Rena as well to seed the big tank.

Question: Can I give the sponges and biostars from the Rena in the 75 a good wash and reuse them when I start it up again or should I get new ones?

I want to order 2 or 3 fish from one place and then plan to quarantine them in the big tank and will move Jack over after a 6 to 8 week quarantine. The alternative is to quarantine 3 fish in the 20 gallon tank, which seems risky.

After that I have offered my 20 gallon tank to a friend who is adopting a 10 year old goldy that has been in a 10 gallon tank all its life. It looks like a stunted comet to me, it has a long single tail, though three lobed. It's got a bent back with a low tail set, but it looks like deformation from stunting, rather than a fantail body type. It's about 4 inches long. If it is given a larger tank and better filtration is it likely to grow much more or will the 20 gallon be sufficient for it?

Ellen

I tiled my 20 gallon with clear glass 1 inch tiles. This one will be 1 cm vitreous glass tiles, not as transparant, but a whole lot cheaper. I posted about the tank in this forum 10-12 months ago.

I stuck the tiles on the glass with a dab of aquarium silicone. I left the bottom tiles loose, not a good idea, the vaccuum rearranges them every time. This time I think I will stick the tiles onto larger 'tiles' of glass and then put those in place-loose on the bottom, spot siliconed to the back. Working with that many tiles (over 10,000, ack!) with my head down inside the tank with silicone fumes is not enticing.

Jack's mosiac tank has done very well for the past year. Algae has grown on it, I wipe it off. Some has grown between the tiles which I can't wipe away, but I think it looks better with a little coating of algae. I'll be using pretty much the same color scheme, but a more detailed picture, on the back and bottom of the tank-water, leaves, water lilies.

Since I took this picture I added some plants in colorful coffee mugs. I've spotted a few pots for the big tank and I'll give them a coat of epoxy before I put them in.

I've got several feelers out for fish-I'm looking for one (very) black ranchu, one calico ryukin (mostly white with little spots of black and minimal orange, with streaky black and white fins (e.g., a smaller version of one I spotted on one website) and the third fish to be determined. Oranda, ryukin or ranchu-probably mostly red metallic, or yellow... or ....
All should be 2 1/2 to 3 inches, about Jack's current size.

Wow, looking at that picture-I knew he'd grown, but it hadn't seemed like that much. He really pops against the tiles.

Ellen