I also give Delta ACV orally. I know you can spray a 50/50 mixture with water and it's supposed to repel fleas... dunno about ticks? I've also heard of using Neem oil. I haven't had Delta on any meds (and we have bbaaaddd fleas here) and I haven't seen one on her yet... a lot of people say a natural diet will allow that to happen., but I still am finding something to put on her. I'm going to buy that best yet stuff or whatever it's called.