Dying GREEN Silver Mollies

Hi guys/ Sue 👍🏻

OK I'm in trouble. As Sue may remember I have silver mollies. The tank is cycled and ammonia 0
Nitrites 0
Nitrates. 20-.40
Ph 7.4
Now my water is too soft I have found for mollies so was gradually hardening it bit by bit. Mollies started to shimmie. I thought fine, this should stop as they get acclimatised to harder water. They have now started dying. Symptoms include (in a sort of chronological order)
Loss of appetite.
Lethargic
Spine scales turning yellow
Quick ish breathing
Shimmies
Swimming erratically and out of balance
All manor of coloured pooh (red,  brown, white)
Some have inflamed gills.
Death
Green on top.

Please help!
Attached picture is minutes after death.

Ps. She was pregnant and all fry died inside her. Looked almost full term

Hi there Sue,

Mollies have been in around three weeks.
Gourami a week.
They look fine. Just generally wandering around looking for something to munch on which at times was a listless molly.
All mollies bar one have now died.
He is newer than the rest as I swapped him for that aggressive female.

I'm gonna just leave the two gourami in there now and keep the water around what they like I think. I changed 40l of the 60l yesterday and syphoned out all of the substrate so I was sure all the pooh and any other decaying matter has been removed as well as any discoloured plant stems or leaves.........

Sorry to hear about your problems, and the loss of your fish.
I have had several steep learning curves during my relatively short time with my gang, though luckily they haven't all involved losses, but have involved a lot more work than expected.
Correct water conditions are very important, and keeping fish healthy is more complicated than most people think.
Keep at it, and best of luck with your remaining fish.

The fact that only the newest molly to your tank is still alive is highly indicative that the problem is the hardness. He has been exposed to soft water for less time than the others. If your area has hard water, that's what they'll have been kept in at the shop which is why they are not dying in the shop tank.

Something shops won't tell you is about matching fish to your water. All you need to know is the hardness of your water and match that to the hardness needed by any particular fish species. The best place for finding the hardness a fish needs is http://www.seriouslyfish.com/knowledge-base/

You said in another thread that you've been using RO to mix with your hard tap water to get a hardness of 6 dH (in ppm that converts to 107).
Of the fish you have/had -
Mollies need 15 to 30 dH, so your 6 was way too soft for them
Dwarf gourami need 2 to 18 dH, so your 6 was perfect for them

If you want to keep the gouramis, I would keep your tap:RO mix at the right ratio to give somewhere around 10 dH, and rehome the last molly. Then look round the shop to see what you like, make a note of them then go home and look them up on Seriously Fish. Any fish with your tank GH in the middle of their hardness range and suitable for your sized tank can go on your shortlist.





On the subject of steep learning curves, I feel I ought to warn you about dwarf gouramis. So many of these fish imported from the far east are already infected with an incurable disease by the time they get to the shop. But no shop will tell you that because then you wouldn't buy them