Zebra Danio - strange behaviour

[Carole and Chris]

Hi everyone - new to this so need your help. Three zebra danios (Snap, crackle and pop!!) in a BIoOrb tank - six weeks in, water settled (tested it!). One ZD bigger than other two, tail and lower fin bigger - is it male/female? Now exhibiting some strange behaviour. Hiding in the plant (fern), usually same place, tail down, head up. Seems to have some balance problem (swim bladder?) and I keep thinking it is very ill. But then it swims off perfectly happy and in full control. So ill or breeding or protecting eggs? Seems to be some ?jelly like? stuff in the moss close to this area - eggs or waste? I thought they fell to the floor and didn't stick to plants. Yesterday introduced three neon tetras (Henry VIII, Beethoven and Sir Francis Drake) but am sure this behaviour had started before they arrived. Probably not the best time but Chris has autism and we had agreed he could add to his pets when he did well at school - he came home with three certificates for outstanding effort!!!! I'll leave you to guess what the subjects were...see fish names!
So please, any advice on if ill what to do and if breeding what not to do.....
Carole and Chris

 

[The-Wolf]

Hi Carol & Chris to the forum

the one with a bigger tail maybe a longfinned variety.
To sex danios; Females have deeper bodies when compared to males. danios are very carnivourus to their eggs and fry so it is not protecteing eggs.
The problem you've described seems to point to swim bladder infection try fish doctor for a diagnosis.

Check out my website for information on Zebras and other danios.
HTH.

 

[Carole and Chris]

Thanks Fish Guru! Had a look at the site you suggested. Thanks. The other difference last week was the heater broke and water got much warmer than usual. Maybe it affected the fan tailed ZD more than the other two?? Should I remove him/her from the tank and try to treat? Only have a small bowl with no filter/air pump so not sure if that will help. Have set it up and treated the water just in case I need it. Help!

 

[The-Wolf]

Thanks Fish Guru! Had a look at the site you suggested. Thanks. The other difference last week was the heater broke and water got much warmer than usual. Maybe it affected the fan tailed ZD more than the other two?? Should I remove him/her from the tank and try to treat? Only have a small bowl with no filter/air pump so not sure if that will help. Have set it up and treated the water just in case I need it. Help!

zebras can tolleate higher temps than 24c/75f for short periods but higher temps means lees O2 in the water and can lead to all sorts of diseases. Long finned are less resilliant to normal danios due to in breeding to get the long fins, so the assumption that higer temp only affected him is prob correct. I woulsd say treat the whole tank, you just never know if the others will come down with it or not.

when buget allows I suggest buying a small tank for hospital and breeding reasons.
good luck keep us posted