wrote in message
...
we are in the process of moving our comets to a larger tank. he's lost
3-4 scales from bumping around things in his now too small tank. will
they grow back?

Yes, eventually. They may be the wrong color (white/clear) but they'll
grow back.

Now that we have to get a larger tank, its location will have to be in
a place that sort of needs to be quiet. Have 2 comets going into a 20g
tank. I always do the regular water changes and skim off the obvious
stuff off the gravel. The noise of a filter may be a problem. Any
major problems not using a filter. I'm going to use a air stone.

In my experience, it's the airstones that make the most noise.
A good -- i.e. expensive ;-) -- canister filter in an enclosed
stand is pretty quiet. I have a Fluval-104 on a 20G, and I like
it fine.

And yes, you probably would have major problems not using a
filter. Certainly goldfish were successfully kept for centuries
prior to the invention of motorized filters, but I suspect they
did _daily_ water changes, and not those piddly 10% things either.