Male molly Sitting at the bottom of the tank

[Lisa017]

Hi everyone,

I have a male sailfin molly, and over the past 4 days he has been sinking to the bottom and when he swims its like he's fighting to stay afloat and he gets tired sits in the stones breathing heavy. But he is also looking very skinny. He is in a small 5litre hospital tank (he has an air stone/filter & heater) and I have been treating him with waterlife myxazin for any potential bacteria problems, I am currently on day 4 of the treatment and he doesn't seem to be getting any any better swimming wise.

He is very skinny so I have been reluctant to fast him as I am worried it may do more damage than good. I am torn between him having swim bladder problems or it is the fact that he's skinny as he does swim to the top for food and I have been feeding 3 times a day to try fatten him up, he does seem to be starting to fatten out a little, his apatite hasn't changed.

I would just like any advice anyone could give me please as I really do not want to lose him. I also purchased some API aquarium salt but I am not sure whether I can use it at the same time as the myxazin as I have never used aquarium salt before.

I also would like to add that I have tested my water and they are all fine
My test results
Ammonia is 0
Nitrite is 0
Nitrate is 25
Chlorine is 0
Carbonate 0
Hardness 75
PH 6.4
The temperature of the tank is 26°c.

Thank you in advance
Lisa

 

[Byron]

I do not have much experience when it comes to disease, so I am not going to comment on the bacterial aspect. Maybe other members will have ideas here. But one critical factor stands out, and that is the GH and pH.

Mollies must have moderately hard or harder water, with a basic (above 7) pH. When kept in soft and/or acidic water, they frequently (almost always in time) develop clear signs of trouble involving shimmies, lethargy, clamped fins, inability to remain upright, lying on the substrate. Any of these. These can be signs of other issues too, but the water parameters here are certainly not doing the molly any good. Sometimes mollies can appear to live fine in such conditions, for several months even, but eventually the lack of calcium and magnesium in the water takes its toll.

GH of 75 is presumably ppm (as opposed to dH) so this is very soft water. And acidic with a pH of 6.4.

How many livebearers do you have? Livebearers all have issues in very soft water, mollies being one of the most affected in my experience.

Salt is often suggested, and all else being equal it will not cause harm to mollies, but it is not hardening the water which is still the prime issue. I've no idea as to how the medicine mentioned works, or whether adding salt would make things even worse. @GaryE and @emeraldking are being tagged.

 

[Lisa017]

Hi byron,

Thank you for replying.

I have 10 mollies 3 of them I have had from fry which are now 3+ years old. And 4 are 2 year old and the other 4 are between 6 months - 1 year. To be honest I've never had any problems with my mollies only this one so I'm not sure why it's just him that's affected.

He is still swimming around and eating normally, he's just very skinny but he looks like he is gradually putting weight back on.

Is there anything I can add to up the hardness of the water?

 

[Byron]

Hi byron,

Thank you for replying.

I have 10 mollies 3 of them I have had from fry which are now 3+ years old. And 4 are 2 year old and the other 4 are between 6 months - 1 year. To be honest I've never had any problems with my mollies only this one so I'm not sure why it's just him that's affected.

He is still swimming around and eating normally, he's just very skinny but he looks like he is gradually putting weight back on.

Is there anything I can add to up the hardness of the water?

Do you have fish other than the mollies? If all you have are mollies or these and other livebearers, hardening the water could be an option. A calcareous substrate is advisable, and there are mineral salts you can buy. Note, "salt" here refers to the salt of various minerals, not regular salt as such. Rift lake cichlid salts, though these may contain sodium chloride but with hard water fish this is less trouble than it is for soft water.

You would be best not keeping any soft water species in the tank if you do go this route.

One of the tagged members may have more to offer here--in fact, I'm certain they will.