Lethargy

[Eolith]

I've had two cases of lethargy in two of my bettas recently. I need help deciding whether they need something special done, if they're unwell or just... depressed?

Jack- He's in a divided, heated, filtered tank with Finn. I've had him for about half a year now. In the past two days he's been just lurking among his plants and won't always come up for his food, which seems strange because he's usually about ready to eat my fingers whenever I open the top of the tank. Finn hasn't been showing any signs of similar lethargy or illness and Jack appears perfectly whole and healthy.

Mochi - I've only had him for a little while, but he's a more extreme case of lethargy... to the point that he will lie on his side and appear dead. I got him from a friend of mine who had become bored with him. He hasn't had a heated tank that's been cleaned regularly... is it likely that he'll liven up once I put a heater and clean water in his tank? I haven't had a chance to set up his tank, so he's been floating in a cup in my five gallon overnight with Hal. I'm actually surprised at how little either one of them have been reacting to one another given that the cup is clear. The five gallon is heated so he's probably warm, but still very slow to move around much.

[Oldfishlady]

To understand-5g divided with two Betta, tank is heated and filtered, cycled, 1 Betta lethargic and 1 betta fine, then a 3rd Betta new but neglected and lethargic.

How much and how often on the water changes and when was the last one, additives used, water temp in the 5g

On the new neglected fish I would start making 100% daily water changes for 3-4 days while in the cup and see if he perks up. But first make 50% water changes on that cupped Betta every 2 hours for 3 changes and then start the 100% water changes if he has been in that water for over 14 days.

I know you know this....but make sure the water temp between new and old water is within a couple of degree of each other and use a dechlorinator with all new water added to the fish if on city water supply.

[Eolith]

Thanks for the advice.

To clarify, Jack is in a divided 10g with another betta (Finn) and he's been the one that I've owned for a while acting a little funky. I do about 30% weekly changes on the 10g. It has a filter rated for a 30g tank and an undergravel filter system, so their water should be practically crystalline.

Mochi is the poor neglected dude currently floating in a cup in Hal's 5g. I'll have his own little 3g set up by this evening. I'm sort of in transition from my dorm room at school back to home... the 10g is at home already and I'm moving Hal's 5g and everything else back today.

[Oldfishlady]

Okay...
Even with the filtration you have and its good, aquariums are a closed system and you will have DOC build up, these organic can be harmful to the fish, you may want to increase your water changes to 50% weekly with a deep gravel vacuum in areas that can be reached to keep the UGF working properly.

Since only one fish in the 10g has had a behavior change....it may be age related, however, I would still QT that fish and start a daily 100% water change on him for 4-5 days and see if he perks up.

[Eolith]

I just got home to find that Jack has a bloated abdomen... which I know is a possible sign of dropsy. I'm going to quarantine him immediately, but I only have so many tanks and I'm going to have to switch him out with another fish.

If it is dropsy... how likely is it to spread to the other betta in the tank and/or the betta that I switch him with?

[Oldfishlady]

Dropsy is a symptom and most common cause if from poor water quality, increase the water changes on the tanks to prevent is the best method.

You can use most anything for QT as long as it is fish safe, you can clean it with diluted vinegar for any soap residue. the bare bottom QT container of half to 1 gallon works best.
You may want to start an Epsom salt 1tsp/gal treatment on him for 10 days along with 100% daily water changes.
Does he look to be pine-coned or scale sticking up or is it just his stomach
Once symptoms of dropsy show up often recovery is poor.

[Eolith]

Yes... he appears to have a very slight pineconing. I know about dropsy and its prognosis... I've done some research. I'll be doing 100% changes daily as suggested along with salt and such. We'll see how much can be done for him.

I feel like a terrible person. Is this really all my fault?

Should I be doing more frequent changes on the ten gallon in the wake of this until I can sort of reestablish better water params or something? Or just continue with a weekly 50%?

I literally just finished doing a 50% change on the ten gallon. Still getting Jack's QT set up properly.