Thanks very much for the info!

I am running a filter but only a small one at the moment because I don't really think the frogs need a crazy amount of filtration in their tank as I keep the water conditions fairly clean by frequent water changes.

I always make sure that when i do the 100% water change that the water has had time to adjust and to heat up, I am running a heater which is currently at 16 degrees, 60F but im thinking that this may not be entirely necessary as its just to prevent the temperature dropping during the cold nights.

I will keep an eye out for the lymnozyme you were mentioning as i know how messy these guys are and a bacterial infection would be a disaster.

Please keep the good info coming, its priceless, cheers. Gav