I have 4 medium sized comets in a 55 gallon long tank and I was wondering if my one lone fantail would be able to live with them. He is currently in a ten gallon tank with one tetra. Would I need a divider or should he just stay in the 10 gallon.

I have one fantail in a 120 gallon with 3 shubunkins and one common, with no probs at all. The fantail is the biggest fish, but they all seem like one happy family. There's also a school of white clouds and zebra danios, and the latest addition is a golden weather loach.
Just make sure the slower fantail doesn't lose out at feeding time. But I'm sure you knew that!
cupoftea

Ak comets- Your already over stocked ,comets need at least 15 gallons each more would be better aswell and for your fantail i wouldn't risk it.... if you want your fish to grow full length then more space will be needed.

Because comet goldfishes have sleeker bodies and can swim preaty quickly for short perieds of times they might get all the food in the tank. I might want to moniter them while they are eating.

Hi.

So long as your are very vigilant about keeping the nitrates down and have an over-abundance of filtration, there really shouldn't be any reason you can't keep your comets, indefinitely, in the 55.

But I stress this again, very regular waterchanges (at least 30-50%, twice a week) will be needed once the comets grow to full size. By then, I think you'll wonder where all the space in the 55 went and want a bigger tank anyway.

If its your fantail your worried about (no company?), why not get a 20 gallon for a fancy tank and put a new buddy through quarentine for your fantail to hang with? Thats exactly what i did. Now I've got a 9 inch comet and a 6 inch shubunkin in my 55(plus cories, pleco and a dojo) and two black moors in a 35 (with pleco and a dojo). Plenty of space for everyone, enough food gets eaten by all and nitrates are controllable.

I'm sure that whatever you do, you'll do it with a keen eye on whats happening and react accordingly.

Any chance of some pics? Good luck with them!

Toothless has very good points, I had 1 comet and 4 commons in a 55 gallon tank for just over a year. I thought they would be fine for a long while, I have since moved them into a 125 gallon just after christmas. It was the only way to keep up with the water and maintenance, these guys are fast growing!!!!!!