The whitespot parasite has a three-stage life cycle which takes up to 20 days to complete in cold water, so treatment must be continued for this long to be effective in normal cases. WS3 (I assume this is the one you're actually using - I don't recognise the name wc3!) is quite a strong medication, so make sure you're not overdosing or it could stress out the fish unneccesarily. The main thing to check is that your water quality is fine, otherwise most disease treatments will be ineffective as the fish will be stressed. A good Aquatic centre/Pet shop can test your water for you if you do not have test kits, but it's a good idea to get the kits anyway. Other things you can do to help the treatment along is raise the temperature by a few degrees (if you have a heater handy) and increase aeration to the tank (as medications tend to reduce oxygen levels).
Many thx for u taking the time to reply so well to my q' i am using ws3 (typo error) and folllowing the correct guide-lines the "ws" has been getting steadily worse but to be fair its only been a week since i started treatment (1 drop per gallon every 48 hours)so ill keep ya posted
Hi . the whitespot issue was on behalf of a friend and as far as im aware every thing seems to be clearing up now although i think they lost 1 fish to it in the end (yet another reason why im being so careful to get everything right with my tank)I think it helped by them adding a slight warmth to the tank seemed to get the healing process sped up a touch ; )_ Daz