Yes borax is safe I use it to wash my infant's cloths, and to make natural play-dough for the kids. Having said that yes it is toxic if eaten-in larger amounts, licked etc by people or animals.
Shodan should not be washing his face with it-however considering his status he could use Brillo pads to exfoliate.
Advantage is over priced and I've always found it to be worthless anyways.
Frontline Plus is decent however it only kills the fleas once they bite and hinders their life cycle on your dog only. You could have just found a single fleas that hadn't bitten yet therefore it was alive-
Frontline doesn't repel fleas.
Many people on here swear by
Minksheen shampoo as they swear it does repel them-I personally have issues with harvesting of the fat from Minks so my dog has a silky coat,
eucalyptus is a repellent-works great in your house spayed as a barrier-it's not especially pleasant for a dog as they have a heighten sense of smell and well it's stinky to us so yeah torturous to them.
Dawn dish soap is recommended over other brands as it has been proven safer on animals (only the plain original blue not the new ones with bleach, scents etc). In reality any soap liquid kills fleas as it suffocates them.
Citrus Oil repels and kills fleas also-same a
eucalyptus oil but it also is annoy to dog's as it is an over powering scent.
Apple Cider Vinegar is a detourant, killer and repellent (all vinegars are) but
{Mother's}Apple Cider Vinegar given to dogs in their water is a a high effect PH balances that makes your dog unattractive to parasites-this takes time however
ACV has multiple other health benefits and I find it to be a miracle cure all no t owner should not be using.
Always remember this-
once you vacuum empty the vacuum bin into and tied trash bag and remove it to your outdoor receptacle
immediately-fleas will crawl back out of your vacuum! Even if you treat the inside of your vacuum bag you are not guaranteeing fleas to come in contact with the treatment in the bag-just take the bag out to your outside trash receptacle (curb side can etc). Fleas can lay eggs out doors and continue hatching for a couple weeks so re infestation is common thus you have to
spend at least 30 days being vigilant and checking, double checking and ensuring you are fighting fleas at the source and not just wasting your energy killing fleas that will be replaced by reinforcements in a few days anyways.
Diatomaceous Earth is magical but not long lasting by itself use it with Nematodes outdoors. (go to your local gardening store or animal feed-livestock farm store)