A bit of a update...
The three remaining seem to be doing fine, and eat fairly well. I still have 2 of them who don't go to the water by their own, and as soon as they have a chance to be on land, they do. The third one, the one that used to spent it's time on water, as been with a unusual behavior that I'm still trying to figure out.
To put it into context, I've changed their aquarium to one a bit smaller but still has about 25 liters worth of water. I've not placed the elodeas in this tank mainly because I think I don't have enough watts/liter to have them on, in the last tank they were holding on but still decaying in a lot of places.
When I placed the newt that used to be in water, she wanders about in the tank, normally, but after some time, maybe a hour or more she will go to the platform. Which isn't a big deal. After some time she will go to the water again, and then triesto escape the water going against the glass and swimming upright. She eventually will climb to the glass. I have no idea why... at first I thought it might be due to the lack of floating plants, so I improvised and made some plastic plants to serve the same effect. But she still behaves the same. I've tried placing her in the tank for 3 weeks now (once every week) with the same results. She's now in a little tub with water and a piece of cork and java moss with the other 2 newts. They do fine as well in there, but she will not behave the same while in there. She will go to the water (shallow but enough to cover her) and won't try to escape. She's the easiest one to feed from all three, and also eats a lot.
In this picture the tank doesn't have the floating platform, but whenever I tried to place her there a floating platform was available.
The tank is well ventilated and I even got a little USB fan to cool the water. In the picture the temperature is 23.4ºC and it was about half a hour after I turned the fan on, it was 24ºC.
My only guess is water quality (high levels of ammonia?), I'll need to buy a test from somewhere where they don't cost close to 20€ and figure that out.
Any advice or opinions will be appreciated.
Cheers
PS: Does the picture appears way to big for you guys or it resizes for your screen?