What could be wrong with my Betta?

[danajs]

How did you cycle the tank, originally?
What kind of test kit are you using?

If the tank was indeed cycled, there's no need for the SafeStart

I moved all of my existing filter media and substrate over and also kept the same decorations, then kept an eye on the parameters using NT Labs Aquarium Water Mini Test (it tests for ammonia, nitrite and pH).

I’ve always used the SafeStart with every water change because it’s works for me. The period of time I stopped using it I had a huge ammonia spike (this was a couple of years ago with my first ever Betta - the one who lived for a good couple of years after that).

 

[danajs]

It sounds to me like there is some kind of infection, pathogen, or parasite that both of your bettas had. It's possible that's what your first betta had and it was passed on to each betta after, since the second betta was in the tank the first betta died in. It's hard to say what it could be, but that seems to be the most likely possibility, since it doesn't seem to be a water quality issue. I would be careful about adding another fish in the near future. Depending on what it was, it can be difficult to ensure it's gone. Maybe just let it stay a shrimp tank for the time being.

I see what you’re saying, but the fact the my first Betta didn’t go in the same way (with the clamped fins and colour loss), would suggest there was nothing wrong with him other than age. He was about 1 when I got him and I had him for about 2 years, so he was around 3 when he died. I’ve also since found out that he was UK Bred, but the two I’ve lost in quick succession of each other were imports. Could this be something?

 

[danajs]

safe start isn't the same as cycling the tank btw

I am aware, I only use this as a booster and because it has always worked for me

 

[danajs]

You don't have cream or perfume on your hands or wrists have you? ? It's really bugging me as to what's going on...why is it just the betta that's being affected and not the corys

Nope, no cream or perfume. I wash my hands before going into the tank and always make sure I keep them under the running water for ages to remove all soap. I know loads of people who haven’t been able to keep Pygmy Corys because they’ve found them so sensitive and with RCS in their too, I would have expected them to show some sign of there being a pathogen or something in the water if that is the case. Although I have now rehomed the Corys, my mum has told me they’re happy as anything in with her Panda Corys and my shrimp are all still going strong too.

 

[danajs]

This has nothing to do with aquarium plants.

Clamped fins are usually caused by poor water quality or something in the water that is irritating the fish. It can also be caused by fungus, bacteria or protozoan infections, although this is very uncommon and normally only one fin is affected and it turns cream/ white.

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Is the water temperature actually 26C, as measured by a thermometer in the water?

If the ammonia, nitrite, nitrate and pH are fine, then you need to look at other things that might be getting into the water. You mention plant fertiliser. What kind, how much do you add and how often do you add it?

CaptainBarnicles is looking in the right direction.
Do you have buckets specifically for the fish tank?
Does anyone else use these fish buckets for anything besides the fish?
Do you use disinfectant wipes or hand sanitiser?
Does anyone use paint, perfume, deodorant, hair spray, or any other aerosol/ smoke in the room?
Do you have anything like moisturising cream, perfume or other chemicals on your skin?

What sort of filter do you have and how often and how do you clean it?

I have one of those stick on thermometers (opposite end of the tank to the heater) and that shows 26C. I have also double checked this with a normal thermometer and both give the same reading.

I’m using Tropica Premium Nutrition and am dosing 1ml per week, which is half of the recommended dose for my tank size.

We have three buckets which are all used for all fish related tasks only. I have my own gravel vac for my tank and I use a 2l jug for filling the tank back up - nobody else uses this jug and it is for fish only.

No to hand sanitizers, creams, perfumes, aerosols, smoking, etc.

The tank came with a built in filter, so I’m not sure exactly what it is. It has a course sponge, a finer sponge and then a cage with ceramic beads and charcoal in, and a spray bar goes over the top of it and it trickles through the layers and into the tank. I rinse the two sponges in the tank water I’ve removed every couple of weeks, depending on how grubby they look.

 

[DragonScales+Doubletails]

I have one of those stick on thermometers (opposite end of the tank to the heater) and that shows 26C. I have also double checked this with a normal thermometer and both give the same reading.View attachment 136763
I’m using Tropica Premium Nutrition and am dosing 1ml per week, which is half of the recommended dose for my tank size.

We have three buckets which are all used for all fish related tasks only. I have my own gravel vac for my tank and I use a 2l jug for filling the tank back up - nobody else uses this jug and it is for fish only.

No to hand sanitizers, creams, perfumes, aerosols, smoking, etc.

The tank came with a built in filter, so I’m not sure exactly what it is. It has a course sponge, a finer sponge and then a cage with ceramic beads and charcoal in, and a spray bar goes over the top of it and it trickles through the layers and into the tank. I rinse the two sponges in the tank water I’ve removed every couple of weeks, depending on how grubby they look.

those thermometers usually read low in my cases

 

[hansgruber7]

You're probably right. It could well be that the second betta brought in a pathogen of some kind that was passed to the next betta.