you could get his urine tested by your Vet to see what his PH is, but the only way to get the urine more alkaline is by wet
food. YOu can also get his
urine sample to see if theres an
infection present at the same time
as far as cleaners, there are a few enzyme cleaners avail at good pet stores is this what you've used? the one I like the best is called Fizz or something its a table you mix with water.
theres also Urine Erase, Natures Miracle etc.....