Neon Tetra help

Question
Hi there, I have 6 Neon Tetras in a 20 gallon long planted aquarium. I've noticed that they are not as brilliantly colored as they were when they were in the pet store. One even seems to have lost all of its color! I have amazon sword, anubias, and crypt plants in the tank. I feed them twice daily, and yesterday's test results are: Ammonia: 0, Nitrite: 0, Nitrate <5ppm. I oxygenate the tank with a powerhead with a rating of 174 GPH. I consider myself at least experienced in the fishkeeping hobby; this is a problem that has puzzled me. I've had almost no problems with my fish - so far, in my 110 gallon saltwater, not a single fish has died in the past 1.5 years. But the neon tetras don't seem to be very active, they don't school, and they're losing color. Help would be appreciated.

Answer
Dear Alexandra,
Faded color could come from something as harmless as stress, to the fatal neon tetra disease. Neon tetra disease slowly attracts the fish internally, and they will become listless and separate themselves from the group. They fade because they get white patches under their scales. In this case, their is nothing u can do but if all your fish are loosing color, then its not this because one fish will usually become infected at a time.  If they all seem to be loosing color at a time, then it is something environmental. In this case, I cannot explain why exactly they loose color, but here are suggestion for things to do to return their color. Even though your water quality is great I would suggest making around 20% changes every other day for a week or so. Also, you should make sure the temp. is at 24 degrees Celsius with a PH of 6.8. You should also make sure the filter is clean and possibly add more carbon. Faded colors can be do to stress caused by other fish, in which case I would remove the fish causing it. If u want u can medicate the tank with MelaFix, but thats up to u because i don't think thats its necessary. hope this helped! if u want anything else let me know. Thanks. Good Luck.
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