S1ren: Your Pleuros are so small because their enclosure is definitely too small for that amount of specimens. In fact, I wouldn't keep any Pleuros in a enclosure that size at all, and would keep even couple of Pleuros at least a three times larger enclosure, and I actually even have had. When I had my own Pleuros about few years ago, they grew up to 20 cm long each and even rather quickly when accommodated in a very large tank. Very same situation happened with the Pleuros of my friend too and his specimens grew up even larger than the specimens of mine when keeping in a tank with holding capacity of 350 litres (I am too tired and lazy to count any gallons right now...). I have to admit that sometimes I remain thinking why so many hobbyist in USA are keeping almost every amphibians in such a small containers as usually been informed and notified by hobbyists from USA, thus usually everything is big in USA. Don't you have room space enough while you have largest appartments and houses in the world?
(btw, it was a joke...) Most of skandinavian hobbyists think that size of the enclosure like S1rens Pleuro-container is extreme minumum for (max) two
Cynops orientalis which are, however, remarkably much smaller (mayby one of the smallest among common captive newts) than
Pleurodeles waltl...
In fact, here in Finland, we have even recommendation laws for the minimum sizes of enclosure for captive animals and for example, it is illegal here to keep e.g. any fish in smaller tank than 40 litres. Actually, as I have understood, it is now illegal even sell smaller aquariums (e.g. gold fish bowls) than that for contemporary accommodation for vertebrates. Laboratory animals, guarantee containers and so on are different cases and separated from this practice of course... In the real life, it is sure that nobody can actually control or monitor that policy here either but the community of hobby here is quite small, intense and closed and everyone is watching "brotherhoodly" after each others in a sense of proper caring and culturing conditions of the specimens of this interest. It would be difficult for us to keep any amphibians in a smaller container than is expected to be a minimum here for some spesific species without any debate or notes from more experienced enthusiasts...
I agree with Jeffrey that the size of enclosure affects a lot and does really matter, what comes with the final size of naturally rather large caudata species like this. As you should know,
Pleurodeles waltl is definitely biggest newt species in whole Europe.
And as you already mentioned, your specimens seem to be sexually mature ones and unfortunately, huge development boost in their size is scarcely not expected in your case anymore. In my opinion, they are not too young to breed and as regards that contents of two last post of yours, you unfortunately have misunderstood the situation. Considering the case of your newts and their age you mentioned above, they should be much bigger in their length and weight at present. So you actually don't have any time to think about bigger tank but you should have had that bigger tank already a few years ago.
However, what is done is done, and I still recommend you to invest for a bigger enclosure as soon as possible. Not because of possible growth of newts, which is unlikely at least in a noteworthy sense, but because of the health and well-being of your newts for now on and in the future...
PS. I really have to regret my poor and disordered English for the native speakers, ones again, but I just have nothing but a blur in my head right now when it's 4:15 a.m. in here -sorry
(Message edited by Aki_Suzuki on February 24, 2006)