Fish Care

Photo provided by original emailer.
If abdominal bloating doesn’t subside after a few days of fasting, the diagnosis may turn to Dropsy.

Q: AC wrote,

I think i have a problem, for the last month my betta has been getting fatter and fatter. Until recently I thought it was just a bit of overfeeding. Then I saw your website and the message from SK on 2.22.2007. I have a very similar problem with my betta, he does not seem to be stressed at all but has a very distended abdomen.

Water quality tests as:
pH: 7.0
Nitrite: 0.3mg/l (a bit high i know so doing another water change)
Temp: 78 degrees
Tank: community tank (2x Corys, 4x minnows, 1x plec & 1x loach) filtered and heated

If you think it is dropsy do you think I should isolate him and attempt to treat it? I’ve seen a lot about epsom salts and possibly antibacterial treatments. Also now that I’ve been looking around for cures I think my bettas (I have one male and two females) may have a case of fin rot as well. Their dorsal, anal and caudal fins all look fine but their pectoral fins are lacking any webbing between rays. Is this normal for bettas? I’ve attached photos of the male with his distended abdomen and two photos that show the state of their pectoral fins. I know this is probably a lot to take in but any suggestions you may have would be greatly appreciated.

A: Thanks for writing in. The photos you provided were excellent quality and very helpful. The first thing I noticed is that all the photos showed severe abdominal bloating. I assumed it was the blue betta that you were referring to regarding the distended abdomen but your white betta is quite bloated as well. Dropsy can spread if the root cause is contagious. For example, if a virus lead to dropsy it can spread from fish to fish if water is mixed or even if equipment is shared. At first glance it does appear to be Dropsy but we should rule out overfeeding first. Can you provide more information on what you are feeding? What type of food, how much are you feeding at a time and how often do you feed? Have you tried fasting the fish for a day or two? Have you noticed them excreting waste normally? If we can rule out constipation then we can turn our focus to Dropsy.

In terms of fin rot I did notice some minor fin rot in the blue fish in the anal and tail fins. The pectoral fins may be showing a little. All the fin rot I could see in the photos was pretty minor. It could be a water quality issue. The presence of nitrites tells me your tank is trying to cycle. That can certainly cause the fin rot you’re seeing. I also recommend doing an ammonia test.

If it turns out both your bettas have dropsy there isn’t a lot you can do but make them comfortable. Epsom salts may help. It’s important to only treat the sick fish by removing them from the rest of the population. Corys, plecos and loaches are especially sensitive to medication and water additives and shouldn’t be exposed to them. I will keep you and your fish in my thoughts. Let me know a little more about the feeding and maybe we can figure out what is going on.

AC: I’ve had the blue fish isolated since I sent you the e-mail and didn’t feed him for 2.5 days, then fed him half a mashed up pea but he wasn’t interested. He has pood a bit but not much and is still very bloated. The other two bettas have been in the tank with my other fish, they get a mix of ‘Aquarian tropical flakes’, ‘King British Catfish pellet food’ and ‘Hikari Algae wafers’. I have 4 minnows, 2 corys, 1 plec, 1 loach and 3 bettas (1 male & 2 females). Daily they get approximately 8 catfish pellets (they all eat these) and 8-10 flakes. Then every other day I put in an algae wafer for the plec. I hope that this will hope with a diagnosis, looking forward to hearing from you.

Thanks for providing the food information. This does help explain why the others may appear bloated. It sounds like they are being fed pretty heavily. Bettas tend to bloat quickly when overfed. A good rule of thumb when feeding bettas is to feed a portion about the size of one of their eyeballs twice per day. Also, make sure they are eating food for carnivores. Of course they do tend to be little pigs and want to eat anything dropped in their tank but foods like algae wafers and catfish pellets can certainly lead to bloating. Their short digestive tracts just aren’t built for it.

Based on your photos and the food info you provided I have to agree with your original diagnosis that your one betta has dropsy and the others are probably ok, just a bit bloated from overfeeding and eating foods not really intended for them.

By the time dropsy progresses to the point of bloating it generally isn’t treatable. You’re doing the right thing by keeping him segregated from the others. As long as he’s active and eating there isn’t much you can do. Just keep his water clean and be careful not to overfeed him. Bettas with Dropsy may continue to live for several weeks or even months before they succumb. The best thing you can do is keep him comfortable and avoid stressors.

Photo provided by original emailer.

This betta shows substantial bloating but was being consistently overfed and fed herbivore foods, which contribute to bloating. Feeding small portions of betta-appropriate food may reduce bloating and rule out Dropsy.

Photo provided by original emailer.