Im afraid that this just isnt true anymore.
What we must do is re-create a wild type UV index and light level as part of a good and well thought out photogradient. We then let the animal self regualte its exposure as it would in the wild.
What you should do is place the canopy on the front half of the viv so that the lighting is towards the front. Then use your decorations and plants at the back and towards the middle of the viv to create shade. This is your photogradient. The crestie then is able to see 100 million colours inc UV when activated by UVA will then adjust its position throughout the day to obtain the exposure that it requires. make sure that the highest basking branch directly under teh fitting is no closer than 15-20cms from the lamp. You can plant right up to the top at the back.
Dont forget that a mesh top will take away 30-40% of the light and energy from light produced from new and this will reduce further still as the metal top rusts and calcifies. You should every month or so remove the mesh top and brush it clean and through with a wire brush to keep the holes a big as poss and allow light to travel through.
Cresties will and do use high concentrations of light. They are clever enough to know where they want to be and will adjust thier position accordingly. If it was too bright they would hide if its just right they will use teh whole enclosure to self regualte through differing levels of energy during the day.
Only last week I visted a breeder that has 12% HO-T5s and reflectors in the viv and the cresties sit 10-15cm right under the lamp for around 6 hours a day. They are huge cresties and amazingly colourful. we wouldnt advise this as a matter of course but it just shows how these animals will self regulate.
The trick is plant your enclosure well, provide areas of high light and areas of cool and shade. Then let nature take over!
As you all know we believe that "All the secrets of great animal care are hidden in the wild animal" this is very true. Just look at the wild climate and ecosystem and do your best to re-create this and you cant go wrong.
High light levels only become a problem if the light is over the whole enclosure and the animal has no chance of self regaultion though areas of shade or leaf scatter illumination.
Im happy to help further of course
Originally Posted by LauraRawr
Hi, you really shouldn't be using anything more than a 5% uvb (through mesh) with cresties as they have very photosensitive eyes and are nocturnal animals. A higher percentage can lead to eye damage and blindness. My advice is to change it when you can =) and report whoever sold you the 12%. A 2% uvb would be your best bet. Cresties enjoy the dark, but if you're wanting to see them out during the day or create a natural day/night cycle a 2% or 5%(max) would be the best.
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