goldfish & possible tail rot

Question
Hello:
I have a 29 gallon tank with two hybred (I think part lion-head because they have a little of that feature on their head) goldfish that are about 5-6 inches each tip to tail.  I do a 25-30% water change weekly and use water conditioner.  I was also using Algae Fix for about 6 weeks but recently stopped.  

I have two questions:  I noticed that one fish which used to be a vibrant orange/red and white has gotten dull and the color is changing to more white.  I stopped adding the Algae fix because I only noticed that change since I began using it.  Could that be the case or could it be something different and is there a remedy?  I feed them Hikari Oranda gold pellets and TetraFin goldfish crisps if that makes a difference.

The other fish is all orange w/white tail but I noticed that the tail now has a bit of black right on the inside of the base closest to the body.  My initial reaction was possible tail rot but when I read up on my goldfish care book it stated that tail rot starts whitish at the tips and eventually can turn black as it gets closer to the base which seems to be bad at that point.  Could this be tail rot, or something else?

Thanks, Amy

Answer
Hi Amy,
My first thoughts wouldn't be that your fish are sick. Color change is a very common thing with goldfish, as they grow and mature, they often drastically change color. The algae fix could have put a little stress on them but then again it could be a coincidence as well. It's best to try to avoid additional chemicals either way. Better algae controls are controlled lighting schedules and an increase in water changes to keep nitrates low.

I don't think your fish with the black on the fins would be anything bad. I don't think it'd be finrot. This is what fin rots looks like-

{Scroll down the page for the finrot pictures}

http://thegab.org/Articles/GoldfishIllness.html


As long as your fish seem healthy and are still eating and remaining active they should be fine. I might try to increase the water changes to about twice a week rather than just once a week. The more water changes the better with goldfish.

Best wishes and I hope this helps!
Karen~