Strange Molly & Platy Behavior: Shaking

[dpm1did1]

I have a nano tank with mixed livebearers plus a juvenile plec and synodontis. One each of the Molly and platy show occasional exagerated flexing of their bodies. I have read that when due to give birth they may alter behaviour such as 'sitting' or rubbing but not 'shaking'. In all other respects everything looks good. Could it be a water quality problem affecting only sensitive individuals ? (looking to buy test kit next shop visit anyway)

 

[aqua_chem]

What size is this 'nano' tank? Mollies need at least 20g, and plecos will need that and more, depending on the species. Same deal with the synodontis, although that will vary heavily on the species. Plecos and livebearers have a disproportionately large bioload for their size. What you are observing might be the effects of over-crowding odisproportionatlyr poor water quality.

 

[dpm1did1]

Agree tank is on small side at 20l but all fish are juveniles/young adult and not fully grown and in time will be transferred to a 300l. Fish temperament is good, lots of Finnage, healthy looking and feeding well. Synodontis and plec also v small and will move as they grow. The odd exagerated movements are in 1 platy and 1 Molly only and are intermittent. If was ok then the mollies would be moved already.

 

[phoenixkiller]

Agree tank is on small side at 20l but all fish are juveniles/young adult and not fully grown and in time will be transferred to a 300l. Fish temperament is good, lots of Finnage, healthy looking and feeding well. Synodontis and plec also v small and will move as they grow. The odd exagerated movements are in 1 platy and 1 Molly only and are intermittent. If was ok then the mollies would be moved already.

I also say that the "Twitching" is an action of being over-crowded and/or poor water quality. I would recommend switching them to a larger tank ASAP.

 

[aqua_chem]

20L is much to small for one platy, or one juvi plec, or even one molly. Do you have any idea what your water conditions are? In bad conditions like this, a number of disease can crop up, which unfortunately is likely what you are seeing.

 

[phoenixkiller]

20L is much to small for one platy, or one juvi plec, or even one molly. Do you have any idea what your water conditions are? In bad conditions like this, a number of disease can crop up, which unfortunately is likely what you are seeing.

Yeah, 20 liters is horrid for a livebearer, and an underlying problem is resulting from poor water quality. I still say at least a 20 gallon tank should be used for livebearers. A 30 gallon would be better, but in your case the bigger the better. So as soon as you can, get a hold of a larger tank. Good luck!