If your finned friend is sick below are a few considerations depending on the sickness:
Fin Rot: The cause for fin rot is a little hard to pinpoint, but a few tips to prevent it are:
- Cut down on the feeding (6-10 pellets a day every other day is plenty)
- Make sure that the water in your tank is warm. This will make the Water Garden more comfortable and will reduce stress which can cause fin rot.
- Be mindful of your decorations. Bettas have very sensitive fins so avoid jagged and plastic accessories.
I also think it's important clean your tank (maintenance video here) and treat your fish with a product like Fish Therapy until he is healed.
While Betta's are very resilient, I typically add a little Fish Protector into any tanks with sick fish or one's that have been handled roughly. It's excellent to use when moving your fish into a new tank.
Swim Bladder: Again, I'd cut the feeding of your Betta in half and fast him (no food at all) at least 1-2 days per week. Swim bladder affects the fish's ability to balance so if your Betta is sinking and unable to swim around that's an indicator of swim bladder. Have you tried the pea treatment? Here's one resource that I've found... all treatments seem to have the same instructions.
You can take your plants off of the tank and water them separately while you monitor your fish.
Finally, feel free to reach out to Home Grown Ponics for a mini refill kit. You can purchase all of their items in various sizes on their website.
Hope this helps and let us know if you have any additional questions or concerns!