I have a problem with fishless cycling which is not addressed by God's Mother in Law Mrs Google. No one has ever been able to show me the formula that shows how many dead prawns or drops of ammonia is equal to two small fish.
Hang in there-- you are doing all the right things for the wrong reasons.
I have done what you are doing but have as suggested used glass and hidden it with rocks and driftwood. Use aquarium safe acid cure RTV and clean the glass with methylated spirits first. I use Sellys as it is the cheapest where I shop but there are other brands that are OK.The main problem with corrogated iron is that the coating (zinc or zincalume) is there as a sacrificial coating and will go into solution in acid conditions. It protects the iron by dissolving first. Newts have very thin skin and are vulnerable to toxins in the water. Stick to glass--no problems. Don't forget to sand the sharp edges off the glass.
They feed on infusoria so you feed them that in the form of green water or additives that encourage the growth of it like a little flake fish food. Some people feed yeast but I find it is easy to overfeed and kill them off.
I sent some boxes this week about 200x200x65mm fastpost for $4.50 each. If they don't fit in a box that size they are V. gigantea and the fine for selling it is about $200000 so the freight will seem negligable. Coil them up round your hand and bag them.
I used to feed them continuously in shallow water for the first week on brine shrimp nuplii. Remove uneaten food daily and water change every time you walk past the tank. After a week or so you can raise the water level.
Double bag in well tied plastic bags with a little air and a teaspoon of water. Send fastpost in a small carton less than 70mm thick and it goes in 1-2 days rather than 3-4 days and costs $3-$4.50.
No leaks
No squashed plants
No angry posty
One happy customer
I agree with DonnaM about the water leval. I have a tank of the same design for breeding red ears and it works well. You need to make sure there is enough height above the ramp so they can't climb out and the more water volume you have the easier it is to keep clean
The word cycling relates to the nitrogen cycle ammonia - nitrite - nitrate. The nitrate is picked up by the plants and the cycle is completed when the plant decomposes. Which plants produce ammonia? How can you cycle a tank without ammonia? The reason you think the tank is cycled with plants is because there is no ammonia produced by plants so there is none to measure.
Don't hit me again boss, Isa workin on it. Get to wet the first lot soon then hopefully into producing a few. I have to agree with Barrie, they are spectacular in natural sunlight.
I always give them as much food as they can eat. I keep my babies in a bare tank and have food in there all the time and any left in the morning gets siphoned out. A good range of food is what I aim for so they get used to different foods.