Mollies Swimming Vertical Help

[Dwashko]

i have two mollies that swim vertical all day and another that stays at the bottom of the tank.  they eat fine and this has been going on for about a week, there not bloated or anything either.  since i noticed ive done 3 20 percent water changes, ive increased the salinty and increased the areation.  
the tank is 30 gallons with an aquaclear 60 and the tank stays at 82 degrees it has several caves and two bubblers.  
5 mollies 
2 angelfish 4 inches
1 clown loach 1 inch
1 albino brstlenose pleco
1 rhino pleco 6 in 
2 goumi
1 rainbow shark 4 in.
the clown loach and the rhino pleco have a 90 gallon that is curently cycling.
what do you guys think, the tank has been established for a year and the last change i made was adding one of the angels almost a month ago.  the rainbow shark is very active and occasionaly chases other fish around but not the mollies. whats wrong with them and what can i do to help them

 

[bluesword23516]

First off mollies need salt in their tank. They might have shimmies. If its suitable for your other fish lower the temperature it's way too hot for mollies.

 

[Lillefishy]

First off what salt are you using? Your other fish especially the loach & plecs won't like the salt.
Most tank bred mollies don't need salt they're perfectly happy without in a community tank.
As has already been said, the temperature is too high for them & they may be struggling for oxygen

 

[bluesword23516]

All mollies need salt, they live in brackish water. They haven't adapted to complete freshwater.  Mollies often get sick because they don't have salt in the tank. 

 

[Lillefishy]

Mollies can live in freshwater, brackish or full marine quite happily

 

[Dwashko]

Im using aquarium salt. Im also gradually dropping the temperature to 75 degrees

 

[Lillefishy]

Aquarium salt will not make the water brackish for Mollies, imo aquarium salt should only be used as a medication ie for parasites.
Using it on a regular basis as a preventative measure can result in salt resistant parasites like us using too many antibiotics we now have resistant super bugs

 

[ech0o]

I have mollies in fresh, brackish, and marine enviornments, they seem to thrive in any.  I am not 100% certain they are sick, sounds like a stress situation.  How aggressive is your rainbow shark?  Are there any tattered fins on the mollies?  IMO rainbows are a bit large for a 30g, ESPECIALLY one as large as 4 inches, that seems to be right about the age they start staking a territories and start attacking fish that enter them, and in that small a tank, that is pretty much the entire tank lol.   It is true that their are some ailments that mollies are more succeptable to without some level of marine salt in the water, like any other freshwater fish.   You could always set up a small quarantine tank, set it up to low end brackish, and acclimate the molly to the QT temporarily, and see if their condition changes, although it would obviously change as well if the problem was stress from the other larger fish.