Hi! I know all about ticks - they are terrible here in Maryland.
K9 Advantix is the only thing that works for us here. It did not work for you? When he was on Frontline, I was finding ticks on him all the time. He ended up coming up positive for lymes disease - but the problem with the test is that it's only 60% correct. So they could have lymes, and not come up for it, OR they could NOT have lymes and come up positive for it. But anyways he was treated with antibiotics for 30 days and now he comes up negative but I get him tested every year along w/ his heartworm test.
There's a couple of natural things out there that I know some have had great luck w/ but I can't remember the names of the products off hand. I can't believe k9 advantix isn't working for you? Are you using the full dosage?
Edit: here it is:
http://wolfcreekranch1.tripod.com/di...rth_fleas.html