Building a viv, maybe with newts

Good morning everybody,
I am currently building a large vivaruim inside of an old china cabinet. And I am still trying to work out what exactly I want to populate it with.
Here is a link to the cabinet build: Lurking no longer. - Vivarium Forums

My original plan was to house red cherry shrimps and snails in the water tank to feed a newt or two, which would spend time between the water and swampy land portions. Then I thought I might add a small frog or two (probably pacific tree frog aka pacific chorus frog) to live in the wet land area that includes some newt territory and the waterfall. Then to really complicate matters i thought I might try my hand at creating a desert on the top shelf for a few lizards if I can find something small enough.

This all seemed like a good plan even if fairly ambitious, until i was told that newts and salamanders are too toxic and that even just sharing water will probably kill the other creatures. This vivarium system holds between 200 and 300 liters of water depending on how full I run the sump, and the fish tank is a standard 26 gallon measuring at approx- 12"x24"x20" tall. I am expecting to put a foot or so of lava rock in the bottom of the sump to give lots of surface area under water for helpful bacteria to grow..

After all that rambling, my question is this: What can I do to make this safe for the different species that will be drinking that pond water? I am not too concerend about poison left on plants from the newts because I am going to have an sprinkler system in there to wash everything down through the soil into the gravel and eventually back to the sump.

Another question would be, Can I grow enough life in the water to sustain a few newts with snails and shrimps? I will have a lot of light on the tank so I expect algae will be blooming like crazy. With my two test bulbs, I turned the water green in less than a day, so I should be able to keep life in the tank, but will newts eat the shrimp and snails?

Are some newts better suited than others to this viv I am building?
Is it an extremely bad idea to do any of this?
Any other ideas or suggestions?

I am still building so there is time to change anything at this point. I am currently just running water and sustaining moss as an experiment to test the pumping and water tightedness of the system.

Thank you for the advice, even the advice I may not like.

edit: of course all predators will be of a similar size so that none of them tries to eat another.

Many of us here are anti species mixing. The first of many concerns that comes to my mind is the very different temperature requirements these newts, tree frogs and desert lizards have. I do no think it would be possible to provide all the species with their ideal habitats in a shared vivarium like this. I think it would be better to pick one species and create a really great vivarium that suites it perfectly rather than trying to accommodate several and only being able to provide mediocre (at best) care for a variety of creatures. To me it sounds like an exercise in frustration to try this sort of mixing.
Also, snails and shrimp aren't ideal caudate foods - worms are more to their liking. I would think, but don't know from any of my own experience, that it would be very difficult to maintain a population of organisms meant as prey/food items in the same tank/vivarium as the predators that are going to consume them without it being a very large habitat. But I am sure others on this forum can provide better advice on this aspect for you.
Your plans do sound ambitious - I hope you can come up with a scheme that will provide the inhabitants with their requirements.The pics you have posted on the link look very nice and I am sure that the final product will be something you will be proud of! Good luck.

Heather

It should be no great feat to heat the top tray while leaving the lower levels cold and damp.
I simply need to keep the airflow between the different temp zones to a minumum and set up some heat lamps shining down on some dark or grey stones to trap the heat. The water will flow under the stones far enough to avoid most of the heat, except for wherever I put the drinking water access. The visible waterfall and the hidden water fall should be able to keep the water nice and cool for the critters in the lower levels.

The biggest dilemmas I am having to get over are my insistance upon growing prey in with the predator and the toxic nature of the newts.

Without any difficulty I can seperate all three sections from each other to keep animals apart but I can't run seperate water systems, those are unfortunately tied into one flowing course.

In the end, I am wanting to set up something that can survive without daily input (interference) from me. (As long as I continue to pay for electricity), The lights bloom algae, something eats the algae, something eats that something and so on.
No animals have been bought, captured or hurt yet. I will be sure that I can make this work before I bring home any inhabitants.

While your idea is certainly the dream of many of us, it´s very impractical.
Temps are a big issue. Most newts require an ideal temperature of 20ºC or less, or significant drops during the winter season (sometimes as low as 3-4ºC). I don´t think you´ll be able to provide the necessary temps for each type of animal, except maybe with A LOT of money xD.
I agree, you´d be better off housing each type of animal separately. Mixing species of caudate alone is largely not advisable. Mixing caudates with frogs or lizards is even more delicate and unrealistic.

I´m afraid the issue of caudate toxins has been exagerated to you. While caudates do have toxins, the water they inhabit does not wecome poisoned by them. The toxins are secreted when the animal is attacked, injured or seriously stressed. It´s usually visible as a white, creamy secretion over the skin. This toxins need to be ingested or become in contact with blood to be effective.
So while housing a newt with a frog will not necessarily mean the frog getting poisoned, it opens the possibility of agression from the frog to the newt which could result in the newt being ingested and possibly killing the frog, or a failed attempt that will cause serious stress and perhaps injury to the newt.
The problem with mixing is always that it is inevitably associated with risks. The reason why most of us don´t recommend mixed species tanks is because we believe that those risks are better off avoided entirely as part of responsible housing and caring for our animals. Obviously the choice is yours, but be aware of the risks! You can find a lot of information on mixing species in the forums and also in the CC articles (check my signature).

As for the newt food. Maintaining a sustainable system in n aquarium is almost impossible. You would require a very large volume and a very small population of newts, and still it is unlikely you wouldn´t need to add food at some points. You can culture certain stuff alongside the newts (like fresh-water shrimp, scuds, snails, aquatic isopods....)but they won´t provide enough to sustain the newt´s requirements. They act as a mere additional source of occasional snacks.

There are plenty of fascinating, beginner species of caudate, if you are serious about keeping some, absorb as much information as you can and take your time. You will also need to stablish what you can realistically care for.

Good luck with your project, wherever it heads to. I wish i had that much fun ahead of me xD

There has been a few rebuilds of this terrarium so far. Lots of ideas have come and gone but one thing is constant, the water temp is too high. The lowest I have seen is 22C, and the average temp being 26C. It is only spring around here so I suspect that when the house gets hot I am going to see low 30's on the average. So newts are ewt.