Yet Another Dead Fish!

[locust267]

OK some of you may remember me posting a few weeks ago about how fed up I am of keep losing my fish, we established that the fish were all rubbish quality from rubbish LFS's.

I've been learning every day on here and am so pleased I found this place as things I got confused about before are now a piece of pie

Anyway yesterday afternoon I found my adult black molly dead on the bottom of the tank - Wheras none of the other fish showed any signs of illness this Molly's eyes, especially one had gone white. She liked to sit at the top of the tank near the water line which looked like she was either gasping for air of drinking! A few of the knowledgable members on here last time assured me my other fish were unlikely to of died from low oxygen but to be on the safe side make sure the filter is making ripples at the surface.

All the other fish seem happy enough. When I bought the fish from the LFS he didn't tell me that molly's needed a little salt and as I have tetra's I didn't want to add any salt to my water so could this be the reason she died/got white eyes?

I currently have 4 black molly fry (think all females) approx 4 weeks old in my 35l tank and have decided that it is best to pass them onto someone who will be able to cater for them so if anyone in the Bournemouth area would like some please PM me. There was every intention in moving them over to my 260litre tank once it's been set up but I would rather now limit the type of other fish I can keep in there.

Any advice on the dead Molly and what to treat my tank with would be appreciated.

Many Thanks

Vicki

*Edit my Na3 and No2 are both at 0

 

[StormySkiez]

I'm not an expert nor have I kept mollys but....I have known others that have and most can be kept in FW w/ no harm. They also thrive in brackish waters like you found out. IMO your molly did not die due to the lack of marine salt. I think it was ill w/ something else. A new molly should have been fine in fresh water and that is probably what they had the molly in at the fish store. It is a good thing for you want to find homes for the other mollies to keep them at their peak in happyness. As for treating the tank, wait and see if any others acting ill. If you have others showing the same signs you may need to set up a quarentine tank to treat them based on the symptoms. Hopefully you don't. I have read that some ppl use melafix to treat all new fish as a preventitive. It is very mild and should not hurt your cycle. Hope this helps and will bring your topic back up so someone with more knowledge will see this as this site has many, many topics and they can get missed easily.

 

[TetraLinz]

A few of the knowledgable members on here last time assured me my other fish were unlikely to of died from low oxygen but to be on the safe side make sure the filter is making ripples at the surface.

If a fish is gasping at the surface, it's not getting enough oxygen. There could be any number of reasons for that - medications being added to the water, ammonia/nitrite/nitrate damage, or not enough surface agitation. In the wild, fish are obviously more prone to aerial or terrestrial predators at the surface, so they don't exactly make a habit of going up there for the view. Making sure the filter ripples the surface doesn't really do much for the oxygen levels - the surface of the tank has to be regularly broken by air bubbles for that, so you could either:

1. Move the filter up so that the outflow disturbs the surface on a regular basis by air bubbles.
2. Add an air pump.
3. Do both

Mollies can be kept in freshwater, brackish or full marine conditions - you've just got to acclimatise them slowly.

HTH (and doesn't offend anyone)

 

[locust267]

I did think about the oxygen but out of all the fish that died this was the only one to sit at the surface and the remaining fish in the tank - 3 danios, 3 neons, 1 rtbs never go near the surface of the water and are always zipping around happily making me think that there isn't an oxygen problem, unless mollies are particularly suceptable to oxygen deficiencies?

 

[StormySkiez]

IMO Mollys are not. The normal tank set up should be fine w/ oxygen.

 

[waterdrop]

I tend to agree with stormy about the individual fish having had or developed a problem. I kept a lot of community tanks in years past and had quite a few mollies. Although I wouldn't labe them difficult fish at all, they did tend to die unexpectedly by themselves sometimes when I wasn't losing other fish. Hope you are successful rehoming the babies.

~~waterdrop~~

 

[Miss Wiggle]

with mollies it's not really salt that they need, it's hard alkaline water, if you add salt then you'll get the hard alkaline water that they need hence people thinking mollies need brackish conditions. My experience of mollies is that if they are kept in soft or acidic water they'll just continually be picking up minor infections and diseases, all usually treatable but all doing steady damage to the fish, eventually they'll pick something up and won't be able to shift it and pass on.

regarding just having one fish gasping, remember that the most common long term effect of ammonia poisoning is damage to the respiratory area, a fish which has been exposed to ammonia (such as a cycling tank) will often suffer with this and gasp at the surface when there is plenty of oxygenation in the tank and the rest of the fish are fine. This can be fatal.

Did you cycle the tank with fish, specifically with this molly that died?

 

[locust267]

No the tank was fully fishless cycled and this particular molly was only bought about 1 month ago and the only 2 other fish I bought from the same shop already died a few weeks ago.

Plenty of people say the LFS is rubbish so I already know not to buy fish from there anymore.

Already have the next LFS in mind for supplying my 260l tanks worth of fish and he's a member on here which must mean something these days