medication are stressful to fish so I wouldn't use both at the same time as your using them as a preventive treatment I would treat with maracyn then follow up with prazipro with dropsy the most effective treatment I have found is aquarium salt 1 table spoon for 2 gallons that will help reduce fluid buildup aid Gill function and add essential kanaplex to treat any possible internal bacterial infections and metroplex in food feeding a small amount twice a day for upto 3 weeks you can use maracyn in food instead of kanaplex if dosing the tank maracyn will only treat external bacterial infections @Gio,