Well, only you can decide if you should take them to the Vet to be treated for parisites. If you decide not to, atleast attemp to eliminate them, as they will when to many, cause lethargy, they will not eat as well, and just a good idea to not be over run by any parasite. I purchased Parazap ! Parazap, runs about 20.00 and can be bought online just type it into any search. It has been used with great results by alot of people on the bearded dragon forum for all sorts of parasites, some swear by it. It is natural and will not harm you lizards, I mix some in their water everyday for 5 days. This can be repeated every month or when bringing in a new reptile, up to you. Like I say it is just an option. I have alot of different lizards, and I try and treat my own as a precaution so they don't get over run ! You can go and read about it and make up your own mind, but do something , as their health will suffer down the line.
Eve