Lost 4 Mollies Over The Last 36 Hours And Losing More!

[vandrez]

I have a 22 gallon tank that was home to six mollies,one angel and two snails for the last 3 months. (The snails were added about 3 weeks ago)However over the last 36 hours My mollies have been dying. I have lost 4 already and the other 2 look extremely sick....

Symptoms:
1) They turn inactive, swim less, stay at the surface of the water,
2) Most of them are found dead on their backs at the bottom of the tank.
3) Some have a white powdery substance (very small amount) on their fins

The angel seems to be doing fine, so are the snails. Please help me figure out what could be wrong and what should be done. I did a 30% water change yesterday after I found 3 dead.

They were all absolutely fine 3 days ago.

 

[roadmaster]

I have a 22 gallon tank that was home to six mollies,one angel and two snails for the last 3 months. (The snails were added about 3 weeks ago)However over the last 36 hours My mollies have been dying. I have lost 4 already and the other 2 look extremely sick....

Symptoms:
1) They turn inactive, swim less, stay at the surface of the water,
2) Most of them are found dead on their backs at the bottom of the tank.
3) Some have a white powdery substance (very small amount) on their fins

The angel seems to be doing fine, so are the snails. Please help me figure out what could be wrong and what should be done. I did a 30% water change yesterday after I found 3 dead.

They were all absolutely fine 3 days ago.

A month ago you were having problems with dying fish and was suggested that you provide water test result's so that other's could help.

Have you since had water tested at local fish store or purchased your own test kit and could provide the results for pH, ammonia,nitrites,and nitrates?
If fishes are being kept in water that does not suit them,they will continue to get sick.
Mollies need hard alkaline water with pH between 7.5 and 8.0, temp around 80 degrees, ammonia and nitrites should read zero on test kit and nitrAte levels would be best kept below 40 ppm with 20 ppm being ideal.
Weekly water change every week of around 40 to 50 percent with fresh dechlorinated water close to same temp as the aquarium.
No pH up or down products should be used but rather straight tapwater with dechlorinator (much easier to maintain stable conditions).

 

[OldMan47]

I am tempted to agree with much of what Roadmaster has said except for one thing. I never heat a molly tank above about 75F and rarely bother to heat one above 72F unless some other fish in the tank needs it warmer. The high temperature may not harm a molly but is simply not needed.
Another factor for some people is that their native tap water is low in mineral content. Common LFS mollies do far better in quite hard water than they do in softer water. The low mineral content water would be close to ideal for an angel while being a very poor water choice for mollies.

 

[roadmaster]

I am tempted to agree with much of what Roadmaster has said except for one thing. I never heat a molly tank above about 75F and rarely bother to heat one above 72F unless some other fish in the tank needs it warmer. The high temperature may not harm a molly but is simply not needed.
Another factor for some people is that their native tap water is low in mineral content. Common LFS mollies do far better in quite hard water than they do in softer water. The low mineral content water would be close to ideal for an angel while being a very poor water choice for mollies.

Have never kept mollies ,guppies below 78 degrees and raised scores of them with no issues. Little ones grew much faster which enabled me to sell them sooner.
Perhaps it was my water but at temps below 75 degrees the platy's and swordtails thrived while the mollies and guppies suffered from frequent fin rot ,fungus,and what could be described as general lethargy. Once the temp was increased for the mollies/guppies, I had way less issues with the two species.
Is whatever works I suppose

 

[OldMan47]

You are right RM, higher temperatures, within reason, mean faster growth and quicker "maturity". I find that I need no such acceleration for my fish and that cooler temperatures achieve a better final quality fish than those resulting from fast growth. Each of us must determine for ourselves what our own values are for fish. Higher temperatures do indeed mean faster growth, faster maturity, younger breeding maturity and shorter life spans. I tend to go in the other direction of letting fish develop fully at a slower pace and I believe that the results warrant my patience. There really is no "best" method. We each must recognize the benefits and limits of our individual methods. If your values say that rapid breeding for sale is good, you will use high temperatures. If, like me, you value healthy slow development to optimal physical condition, you will favor lower temperatures. I have far less fish to sell in a given year than people who use higher temperatures, but the results fit my own prejudices.