Thank you for waiting. I suspect you got your original information on care from a pet store or for one of the inaccurate websites out there. Most people do. While we should be able to rely on such information, unfortunately, it is often wrong. They sell people the wrong lighting, advise the wrong foods, and often don't know the correct temperatures for the various reptiles. After months or years of things not being quite right, the animal becomes ill. Much of what you have been told is wrong. Even though you have been trying so hard to keep him healthy, when you didn't have correct information to begin with, things are going wrong. I'm going to give you some measures to take.
First, yes, soaks are very important. Buy some Pedialyte (yes, the kind for human infants). Prepare a shallow bath consisting of 1/2 water and 1/2 Pedialyte. Soak your skink for about 20 to 30 minutes twice a day. Reptiles can absorb the electrolytes and fluids through their vents (where droppings pass out), so make the water deep enough to cover the vent. Be sure to supervise closely.
When you get home, check the temperatures and adjust them if necessary. The temperature gradient in the cage should be 85° - 90° F with a basking spot at 95° - 105° F. At night the temperature can be allowed to drop into the mid-sixties.
I would get rid of the walnut substrate and the heated rock. Both of these products are dangerous. Pet stores often recommend a loose substrate, but it does frequently lead to serious health problems, including impaction. It’s also a leading cause of eye infections, respiratory irritations, and skin problems. Just because it hasn't caused a problem so far, doesn't mean it will not in the future. I compare it to distracted driving. Someone may do it for years without having an accident, but that doesn't mean it's not dangerous. For more information on substrates:http://www.anapsid.org/substrates.html
Lizards do not have very good heat sensors on their undersides. That means even if the heated rock is maintaining the temperature it is set on, burns can result. The lizard simply doesn't know when its underside has become too hot. Sometimes a lizard can go for years without a problem, but often it's only a matter of time before a burn occurs. A burn would cause the skin to blacken on the part of the body that was on the rock too long, and of course it would be painful. Pet stores recommend these rocks, and at first glance they seem like a good idea. Pet store staff get their information from literature put out by the manufacturers of heated rocks. Here is a nonprofit site where you can read the truth:http://www.anapsid.org/hotrock.html
Also, take a look at this video:
If Tango has never had a UVB light before now, he may be suffering from Metabolic Bone Disease (MBD). It takes months to years to develop. With the right care, MBD can be reversed if it's not too advanced. The UVB light must ahve an output of 10%, and should be on for 12 to 14 hours per day. UVB bulbs must be replaced every six months. They may still look fine after that, but don't emit enough UVB rays to do any good. You'll also need to dust Tango's food with plain calcium powder. Calcium is the other factor in preventing MBD.
Don't force feed. More often than not, that leads to aspiration into t he lungs, which is often fatal. Instead, after tango has a couple of long soaks, you can try another method. Buy some plain meat baby food. Drop a small dollop right on the end of his snout. Many times, they'll lick it off.
The above measures may help, but from your description, tango is quite ill, so it would be best to see a reptile vet. This link will take you to a directory of vets:
If you have more questions, just let me know by clicking on REPLY. I hope you'll be able to restore Tango to health.
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