Mollies

Brendanpat

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Hi . I have a problem with some fish dying . I have some gubbys swordtails mollies amongst others . My black Mollie showed signs of trouble and died . Yesterday a gold one started the same . It was nearly dead . So yesterday morning I filled a bucket of tap water . Treated it as usual and put him in there just to see if it would help . We went away for the day and when we got home I expected him to be dead . But he was back full of life !I put him back into tank last night but hes in trouble again this morning. Tank water tested fine . Help ?
 

AdoraBelle Dearheart

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I have a 54 litre tank with filter and heater . I have about 10 tropical fish . I keep it at 24degrees . I change 10 litres of water every week . And feed once a day . ?
What are the results of your water tests though? For ammonia/nitrites/nitrates?

It sounds like a pretty heavily stocked tank, swordtails and mollies are pretty large fish, and your tank isn't huge, and you do relatively small water changes. My first guess would be that your experiencing ammonia spikes or very high nitrate levels, and this is what is killing your fish. The clean water test reviving the molly lends evidence to that theory.

How many of which type of fish do you have in there? You said among others, what are the others and how many of those? And is it a new tank? If it's pretty new, there's a good chance it isn't fully cycled yet.
 

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What do you mean signs of trouble could you advise what happened? Did it gasp for air at the water surface or was stilling on the bottom of the tank??
 
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Brendanpat

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What are the results of your water tests though? For ammonia/nitrites/nitrates?

It sounds like a pretty heavily stocked tank, swordtails and mollies are pretty large fish, and your tank isn't huge, and you do relatively small water changes. My first guess would be that your experiencing ammonia spikes or very high nitrate levels, and this is what is killing your fish. The clean water test reviving the molly lends evidence to that theory.

How many of which type of fish do you have in there? You said among others, what are the others and how many of those? And is it a new tank? If it's pretty new, there's a good chance it isn't fully cycled yet.
I have the tank set up about 4 months now . I'm still pretty new to it . This was happening when I had only 6 so I thought the over stocking wasn't the problem. I have only 1 swordtail . It's the biggest . I added 2 cory catfish yesterday hoping they would help clean the gravel an 2 ancistrus and 1 tiny endless livebearer I think it's called.how much water should I change ?and what levels are ok of ammonia and nitrate ? I'll have to test again tonight. I think its 12 in total now but I only added them new ones yesterday. This was happening when I had only 5 or 6
 
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Brendanpat

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What do you mean signs of trouble could you advise what happened? Did it gasp for air at the water surface or was stilling on the bottom of the tank??
No its was just lying at the bottom and tilting over on its side sometimes . Didn't seem to be gasping just breathing slowly
 

Aussie_Bristle

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ammonia and nitrites should be 0 at all times, nitrates should be no higher then 20ppmthe less the better.
Corydoras are a shoaling fish and should be in groups of 6 or more. Gravel is to harsh for there little barbs and can cause damages and infections, sand is a preferred substrate for the little guys as they filter through their mouth and gills. I’d be doing a 75% water change and make sure the water is de chlorinated before adding into the tank. When you do the water change wipe down the insides of the glass with a clean cloth.
 

essjay

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Whenever fish start acting oddly, the first thing to do is check for ammonia and nitrite as these can kill fish quickly. High nitrate weakens fish so checking that too is important, especially with so many fish in a small volume of water.
 
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Brendanpat

Brendanpat

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ammonia and nitrites should be 0 at all times, nitrates should be no higher then 20ppmthe less the better.
Corydoras are a shoaling fish and should be in groups of 6 or more. Gravel is to harsh for there little barbs and can cause damages and infections, sand is a preferred substrate for the little guys as they filter through their mouth and gills. I’d be doing a 75% water change and make sure the water is de chlorinated before adding into the tank. When you do the water change wipe down the insides of the glass with a clean cloth.
 
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Brendanpat

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I always give the glass a scrub with the sponge on the handle I got . Really that much . I thought 20 percent. So 75 percent every week ? I've rinsed my filter about twice . Should I keep it dirty or clean it more often ?
 

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If you rinse your filter it should be with tank water. The bucket or container you have taken out the water in is fine to rinse in. Filter should be rinsed and cleaned every couple weeks
 
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Brendanpat

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If you rinse your filter it should be with tank water. The bucket or container you have taken out the water in is fine to rinse in. Filter should be rinsed and cleaned every couple weeks
OK thanks for your help .Thats what I do use . I raised my filter higher so it has more of a drop down to the water creating more bubbles in the water . Does this help to but oxygen into the water ?Any tips on how much to fed . It's hard to get information on the right amount?
 

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