It looks like you have a few spray on remedies in the UK. Reptile Relief/Spray is, also, available here in the state and is effective. I found a product that has the same active ingredient (Permethrin) as our Provent a Mite that should be effective called Net Tex Mite Kill Spray. I, also, found a product called Reptile Callington Mite Spray. I am not familiar with the active ingredient so I can't comment on it. It did get good reviews on Amazon. Just follow the directions on the can/bottle. You'll need to take your snakes out (yes, I would treat both), let them soak in water, clean the cage, freeze or throw out any wooden cage furniture, treat the cage according to the directions, Then follow the directions on what to do with the snake afterward. Reptile Spray can be used directly on the snakes before putting them back. I wouldn't do that with the other 2 products. Keep your snakes on paper while treating them and repeat treatment as directed on the can. Zoo Med Mite Off and "natural remedies" such as garlic oil and olive oil will not work, you'll never get rid of the mites that way. Good luck!