Urgent Mollies bent in the middle

I am very new on this site. I have had tropical fish before. I am now getting back into tropical fish again. I need fast help. I have a few mollies, swordtails and guppies in a cool, fairly small tank. I have to do, fairly big water changes daily. The fish are not happy. They don't eat much.

Problem is: the mollies are starting to look like their spines or tails are broken. They are bent in the middle to lower area. I am trying to treat the problem with fugus remover. And more water changes. There is no plants or anything except fish in the tank. I hope to buy a water heater tomorrow. I am also treating the problem by offering more variety of food, in case it is a vitamin deficency.

 

The bending is a sign of a feeding deficiency most likely caused from the overcrowding.

I would definitely look into increasing the number of tanks or decreasing the number of fish.

 

Thanks

Should I stop using the fugus medicine on them? I hope to be able to get another tank soon. Maybe I can spread them out more.

 

Yeah go ahead and stop. No need to add anything if it won't work.