sick male fighter fish

Question
QUESTION: Hi i wondered if you could help me, i bought a 60L fish tank with a marina filter system and temperature gauge. We set the tank up and let it cycle before adding any fish and have had a happy aquarium for about 2months now, we have 1 male fighter fish, 2 platties, 3 glass catfish, 1 butterfly fish, a silver finned shark and a tropical frog. Lately the no2 levels have been high and i have been doing regular 20% water changes to get these levels down, i have also bought some tetra aqua nitrate minus and have so far used this once.
About 3 days ago our fighter fish became very sluggish and i noticed he is either laying near the top of the water around the heater or the filter pump or at the bottom of the tank wedged between the gravel and a hole in the log ornament we have. when you look at him around his mouth it looks as if he has lost his red scales and toward the back of his body it looks very slightly swollen and his red colour is pale. He is from time to time darting around the tank rubbing up against the ornaments and sides of the tank. I haven't seen him eat much the past couple of days either. He normally hangs around with our platties and often breaks up fights between all the other fish but hasn't been interested in anything lately. His fins and tail look normal but he doesn't fan them out much these days when he is swimming around. our tank temperature is set between 25/26 degrees c (77-79 f) we feed out fish nutrafin max tropical fish flakes and condition our tap water with interpet bioactive tapsafe when we are adding it to the tank, i also test ever batch of water we add to the tank with test strips to make sure it is safe.
i went to our local fish shop and they advised i use an anti slime and velvet treatment which i added to the water 2days ago. i hope you can help me make my fish better.

ANSWER: Emily,

With a tank that small, your are a bit over crowded. If he is scraping himself, that usually means parasites. Does he, or any other fish, show any signs of Ich or velvet? Flake foods are not good for Betta's. Its best to feed him Betta food, which comes in pellet form. Try to keep the water temp steady. Fluctuations can harm a fish. Do not add any medication to the tank unless you know what is wrong. Unfortunately, most large chain pet stores do not know how to take care of fish. Remove the Betta from the main tank and put him in your hospital tank. This will make treatment easier and hopefully not contaminate the other fish. You can try salt water baths with the Betta. I have found these help out a lot since I do not like using any chemicals in my tanks. If you need help with the baths, let me know. If he has Ich, heat/salt treatment is the best, quickies and safest way to go. I will help you with that too if you need it. Let me know if you find any white spots on the fish or if there is gold or copper "dust" on them. I will wait to hear back from you.

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QUESTION: Hi, I've have had a look at our fighter fish and he doesnt have any white spots on his head or body but he does seem to have a dusty looking appearance to his body, which i believe may be velvet? no other fish are showing signs or symptoms of this. could you help me with how to do salt water baths if this is the right treatment, also if i move him to a different tank would i need to add aeration tablets to the water as i do not have a spare airpump/airstone?

Answer
Emily,

VELVET DISEASE (Oodiniasis) is caused by another infecting protozoan (Oodinium) like Ich and is spread in the same way.  It appears first as a yellowish, patchy, granular mark along the body of the fish.  It looks like golden pepper or sand and spreads rapidly.  The white pustules are small and Oodiniasis is a little easier to cure than Ich, since the life cycle is not so rapid. It commonly follows chilling or stress caused by transportation, water changes or poor water quality. Infected bowls should be drained, cleaned and washed in copper sulphate solution and then rinsed.  "Protozin" is also effective against Velvet  "Maracide" by Mardel Laboratories and "Super Velvet" by Aquatronics are similar US products.  Older remedies included the use of Acriflavine and Mercurichrome but these pharmaceutical dyes should not be used since they contains mercury- a toxic, heavy metal that is poisoning our planet's environment and waterways.  "Argyrol" is another US product that is used.

These medications are the best for helping with velvet in a Betta. If he is in a community tank, you will need to treat the whole tank. Velvet is very contagious so it's best to treat everyone. Hope this helps and if you have any more questions, don't hesitate to ask. Since he is a Betta,  no filter is needed. Adding an air stone will help because a lot of medications reduce the oxygen in the water.