Colu

I think this is due to long fins it can takes a lot more energy to swim and long fined varietys are more prone to scoliosis and other spinal issues that can causes odd swimming patterns he might just be weaker than the others I would just monitor for now I don't think medication would be of any benefit at this point

That looks like epistylis that feed's off of the gram negative bacteria on the slime coat of your fish and spreads more quickly at higher temperatures the most effective treatment is a combination of ick x to dose the tank and maracyn2 in food feeding a small amount twice a day for upto 7 days if there not eating dose the tank with maracyn2 or kanaplex @tetra

I would treat the whole tank with expel p I would do a minimum of three full course of expel p it can take upto 4 course of expel p

Forgot to add feed the medicated food for 3 days then repeat on days 14 and 21

Flubendazole is harmful to shrimp and snails it can kill snails months after treatment it can leech from wood and rocks in the tank for a couple of months after treatment you can add it to food he's a medicated food recipe

Yes one tablet of jungal fungus clear fizz tabs for 10gallon the amount nitrofurazone in the jungal fungus clear fizz tabs is under dosed so adding it daily coupled with the 25% water changes in my treatment plan won't harm your fish just do a large water change before you start treatment and add an extra air stone during treatment

I would do the two more days of Epsom salt baths the medication you have such as para guard and ick x don't treat internal parasites or Gill flukes I would holed out for the expel p

I have used aquarium salt at that level multiple times with out an issue that shouldn't causes an issue for rainbow fish when I use aquarium salt I desolve it in a jug of warm water before adding it to the tank and eventually distribute over the surface and always add an extra air stone aquarium salt can only be removed though water changes is it possible you accidentally over dosed the salt

Sorry to hear that at least you did everything you could for her

With mast mortality I would be concerned about cleaning products or air freshener getting into tank at certain times of the year water company will flush there pipe with higher doses of chlorine chloramines did you do a water change the day before they died and did you add a water dechlorinator like prime @Brooke B

Could be a parasitic infection with some of the symptoms your seeing I think it would be worthwhile doing @Odd Ducktreatment protocol for parasitic infection @beastie

The body Shape reminds me of a blood fin tetra

Could be swim bladder with what your describing and looking at the video for the swim bladder you would want do Epsom salt baths 1 table spoon for 2 gallons for no more than 15 minutes for 5 days as Epsom salt acts as a muscle relaxant to help relieve pressure on the swim bladder and for the eye issue I think it would be worthwhile doing a course of kanaplex that's a broad spectrum antibiotic treatment and an extra air stone during treatment @wyrmiii

No I don't think it's velvet here's a picture of a fish with velvet for comparison

As the bloating is only on one side it's more likely to be an internal growth or tumor they are really common in Bettas the fact that the bloating hasn't improved with a change in diet Epsom salt baths and medication it might not be something treatable you have two options keep treating or monitor her and make sure she has a good quality of life and make the decision to humanely euthanize her when you think she no longer has a good quality of life that could be further down the road clove oil is what I use when I have to euthanize a fish you can also get a product called koi sedate that is also used to humanely euthanize fish @HelplessNewbie

Can be more indicative of wasting disease that caused by internal parasites like nematode or tape worms fish can also become emaciated thought bacterial infections viral infections due to the amount of energy needed to fight off the infection and can stop eating and rapidly lose weight

You could use either kanaplex or maracyn kanaplex predominantly treats gram negative and some gram positive bacterial infections maracyn predominantly treats gram positive and some gram negative bacterial infections if you have kanaplex to hand do a course of that with the salt if your seeing not improvement or it gets worse give us an update

What I would do is a course of maracyn and keep the salt at 1 table spoon for 2 gallons for another week

As you have seen no improvement with kanaplex it could be a parasitic infection such as fluke's causing the over production of the slime what I would do is start treating with prazipro once every two weeks for total of three full course of treatment

What I would Do is try Epsom salt baths for 5 days 1 table spoon for 1 gallon for no more than 15 minutes if your seeing no improvement then I would do a course of expel p once a week for 3 weeks

Some disease such as neon tetra disease dwarf gourami iridovirus can lay dormant for upto a year before you start to seeing symptoms most parasitic or bacterial disease can't survive longer than 4 weeks without a host that why every fish I get has a minimum 4 week quarantine period if I see any symptoms I treat and start the quarantine period over again for another 4 weeks from the end of the last treatment

Could be having issues giving birth or internal parasites any rapid breathing hanging out near the surface lethargy flashing spitting food out @ShineOn75

None of these medication contain copper I would only use medication if you see any symptoms I usually quarantine for a minimum of 4 weeks and monitor to make sure everyone is active and eating ok if I see any symptoms then I treat with the appropriate medication

Any rapid breathing hanging near the surface loss of appetite