Dead molly

[Mundle]

My Molly got really fat and then died the next day
It was a male
All other fish are normal
I'll get water tested tommorow
What happened

 

[librarygirl]

Sorry about your fish. Hard to say without more info:

what size tank?
what other tank mates?
water parameters (ammonia, nitrite, nitrate)?
what's your water change schedule (how much and how often)?
what do you feed and how often?
Temp of the tank?
How long has the tank been running with fish? Is it cycled?
have you added anything new to the tank recently (fish, etc)?

 

[Mundle]

60 litre
Guppies
Molly
Blue ram
Neon tetras
Water change once a week 25%
I put in water conditioners
Tank been running for ages
Water test tommorow hopefully

No new fish
Heating 25-27

Feed every second day alternate btw flakes and bloodworms

 

[librarygirl]

60 liters is just shy of 16 US gallons. You didn't say how many of each fish you have but 16 gals is really too small for all the fish you have. Overstocking and overcrowding can cause stress to fish which leads to disease. Did the fish have scales that were sticking out (pineconing) or was it just bloated? It's really hard to say; could be dropsy or another disease, could have been a swim bladder issue from the food.

I'd say start with a 50% water change (use dechlorinator of course). Have your water tested (getting your own liquid test kit would be a great idea if you can, the API Master is best) to rule out any water quality issues. Keep an eye on your other fish. You should also really think seriously about either upgrading to a larger tank or rehoming some fish. Keeping a water change schedule of 50% weekly is a good idea too and vacuum the substrate regularly; clean water can do wonders for fish especially in overcrowded conditions but you're really going to need to upgrade.