My male alpha molly fish died strangely

[your bro joshi]

Dear all i don't know what happened my water quality was some what detoriated or may be because of other reason my male alpha molly fish (silver saiffin molly) died yesterday. Other fishes were doing nicely except my black female molly whose fins were closed and wobbling in water. My silver molly was the boss ( alpha male) and very healthy don't know what happened. I had 6 mollies and 2 guppies in total in my 10 gallon tank. Other than black molly everyone is healthy. Excess bio load might be the reason but why my other fishes didn't died? Is the question. Please help

 

[nirbhao]

What are your parameters now? Some fish are more sensitive than others.

 

[Potluck]

Well that many fishes in a 10 gallon is going to be a huge bioload, what filtration do you have like gph, is it cartridge, or 3 stage hob?, do you have the money to upgrade to at least a 20? Also mollies even though they are found in freshwater streams are also found in brackish waters, most experienced keepers do add aquarium salt because it raises the ph and hardness of the water giving them their more natural habitats. I'm not to familiar with mollies or guppies as I don't keep them cause if their spawning rate, how long was the males dorsal fin? Reason I ask is because they can get huge which will cause drag when swimming so they tend to not swim as much, this didn't lead to his passing just curious, my recommendation is to increase the filtration if you can't afford the upgrades for a 20 gallon, I would steer clear of cartridge filters, if you decide to go this route do not remove the old filter let them both run, I would recommend a aquaclear 20/30 as you have a huge bioload, 25-30% water changes weekly treated with prime, so if you do a 3 gallon water change you would treat the new water before putting it in the tank with .3-.5 ml of prime or 6-8 drops.

 

[your bro joshi]

I have cartridge filter and I also run sobo air pump with two air stones. Sadly I don't own water test kit hence can't give pH level. I change 20℅ water per week. Thanks potluck

 

[Potluck]

The most important part of fish keeping is a test kit
Api Master liquid freshwater test kit

 

[your bro joshi]

Gonna buy after credit of salary in my bank account