Dehydrated and under weight, help plz

[cjbulloch]

Long story short...

have taken on a garter snake who I don't have much history on.

m/f=?popped looks to be female
2ft in length
2.5 months ago weighed 80g
got treated for mites with frontline
would not eat in the 2 months (in someone elses care)
Did not shed in this time. Lost weight, is 38g.

Weights 38g -has been in my care for 2 weeks now, has not lost any more
Has been getting tube fed rehydration salts mixed with water at 1ml everyday
Has started to pass very thin urates 3 times in the past 5 days
Its belly scales are smooth and glossy but its ventral scales are all rough and dry. There is excess skin but is only noticeable when pinched.

I'm worried it'll die if fed and is still dehydrated.

How long will i have to keep giving the rehydration fluids?
When should I start to feed?

Has seen vet, dont know whats wrong

Set up with me - 15 litre rub, temps measure with ir gun 27 hot spot 22 cool, on stated heat mat, for the first week hide had spag moss misted when it dryed, on kitchen roll now.

Could anyone identify the morph? It was fed 24 hours ago a liquid solution with chicken, calcium, liver, heart, rehydration salts and fish oil, Still Alive, what do i do next???
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