Wazine can be put in the water but only kills adult roundworms and needs to be repeated 10-14 days later and there is an egg withdrawal period I believe which is going to be significant with 2 applications that far apart, so almost a month of chucking eggs!
There is a new wormer on the market which is called AquaSol which is also dispensed via drinking water and I believe that may have no withdrawal period but it is rather expensive from what I have read and may not be effective against tapeworms.
There is a new wormer on the market which is called AquaSol which is also dispensed via drinking water and I believe that may have no withdrawal period but it is rather expensive from what I have read and may not be effective against tapeworms.