Permanently ill betta

[Scrumpy]

I need some advice please.
I've had my male betta for about 18 months. He lives alone in a 5 gallon planted tank with lots of places to hide. The tank has a bio wheel and filter plus a pump with tiny bubbles. I keep it at 26/27 degrees, and there's a light for about 8 hours a day.
Water parameters good...ie 0ppm for ammonia and nitrite and 2-5 for nitrates.
I treat him very carefully...I change his water frequently and always use water conditioners and add the correct quantity of aquarium salt. He eats a good quality betta food and frozen bllod worms sometimes.
Anyway...he's always getting tail and or fin rot. I think it's bacterial because there's never any sign of fungus.
The first time he got it, I noticed his full tail was slightly ragged one day...and two days later despite starting to add melafix it was entirely gone leaving just a stump. I expected him to die but he didn't and gradually his tail started to regrow. Now it gets to about 1 cm and them starts to dissolve again.
Then his fins started to be involved. I've been using interpet anti fungus and fin rot because melafix doesn't seem to help...and I think he hates the medicine. I'm careful about how much I use but while it's in the tank he won't eat and hangs, stuck to the side of the filter apparently dead for the duration. When I do a water change he's back to normal. It feels so cruel but it's the only thing that works...until the next time a few weeks down the line.
I have no idea what I'm doing wrong. I've kept a large community tank for nearly 3 years and had no disease.
I treat him so carefully.
Parts of me wonders if I should euthanase him because he's always raggedy finned and seems sad no matter what I do, but I'm fond of him. He comes to see me when I go to the tank and he struggles so hard to stay alive and grow his fins back each time. I just don't know how to stop the infections...I can't think of anything else to try.
Thanks for listening

PS I've tried him with salt, without salt, with permanent low doses of melafix, without, changing more or less water (currently about 15% twice a week), lights on, lights off. You name it I've tried it

 

[wayne]

What's the most water changes you've tried? Ever tried just stopping the meds, stopping the salt and just changing a litre every day or twice a day. Litre out, litre in (with dechlor as required) - works a treat for fry.

 

[Scrumpy]

I've done about 50% every 3 or 4 days for a while which seemed ok but it's a big job to do so often. I don't mean to sound lazy, but if ammonia and nitrites are low is there any need? It didn't seem to make any difference anyway....or if anything increased the nitrates which are high in my tap water. The plants in the tank use it up. I've wondered if I should do fewer water changes because of the nitrate surge....though this latest cae of fin rot seems to have been brought about by my not changing the water for two weeks because I was ill. The parameters are still good though.
I didn't use salt the first 6 months or so but started using it because of the fin rot. I've tried not using meds but his fin rot accelerates.

I'll try your litre a day suggestion Thanks

 

[Purple]

Silly question - but it has to be asked - did you take out the carbon (if any) when using the meds.

Next up - going from a bit of tail rot to almost no tail in two days is really something. I reckon this can only be caused by one of two things - extremely bad water conditions (which I doubt), or somethings eating the little fella. Take a good look around in there, see what happens when the lights go out etc. I accept it's equally unlikely that you don't know what's in your own tank - but nonetheless, something has to be doing this to your fish.

If you still come up blank - and given that he seems to respond to water change for the better - then bag him, and completely re-do the tank. Nuke the lot - new substrate, plants, ornaments - everything. Not as much of a nightmare as it sounds if this is only a 5 gal.

Better to lose a tank than to lose a fish.

 

[Scrumpy]

I don't have carbon in the filter.
The only tank mates he had were some pond snails but I zapped them a few months ago with a complete tank breakdown and clean out. I thought maybe there was some bacterial infection they were carrying. They came in on a java fern a year ago and were multiplying.
Thanks for the suggestion. I could try another tank sterilization but tbh it didn't help before.
I appreceiate everyone trying to help

 

[Quagaar]

Theres more going on in your water than just ammonia and nitrite. If the fish is constantly ill, hes either stressed (stress leads to lowered immuno response) fed a poor diet(again reduces immuno reponse) or isnt having his tank maintained correctly. It could even be acombination of all of these things.

Do you wash your hands 220 percent b4 going in his water? DO you use air freshners, polishes anything with high odour near his tank? Hand creams, nail varnish? perfume? All these can casue illness.
As for water changes, when the fish is ill, diease bacteria will multiply in the water, more frequent water changes will help with this.

 

[izabeau]

Betta's have a tendancy towards developing fin and tail rot, usually fungal, but sometimes bacterial. Mine seem to get it all the time...melfix is great as a soothing agent, but really doesn't fix the problem. you need to medicate the tank with something that treats both F & B rot. you can add the melafix as well if you like. sometimes they survive, sometimes they don't. a 5 gallon tank is fine, just make sure you are keeping ALL your levels at 0.0 and clean the water regularly. I usually do a 50% water change once a week. Hope this helps! Good Luck!!

 

[Scrumpy]

Thanks for the advice.
I've been keeping fish for a few years now so I know about minimising stress and not using air freshners, washing hands thoroughly etc etc. Also I'm using good quality foods plus frozen blood worms.
I'm going to keep up a much stricter regime of water changes for the next few months and see if it makes a difference.
I've had to leave the water for a week while the meds are in but I can change it tomorrow. Poor little chap looks like a femal betta atm!
I'll let you know how I get on...but I don't hold out much hope.