ParaGuard is the only fish and filter safe aldehyde based (10% by weight) parasite control product available. Unlike highly toxic and difficult to use formalin based medications, ParaGuard contains no formaldehyde or methanol and will not alter pH. Parasite Control for marine or freshwater aquariumsContains no toxic methanol and will not alter pHSafe alternative to formalin ParaGuard employs a proprietary, synergistic blend of aldehydes, malachite green, and fish protective polymers that effectively and efficiently eradicates many ectoparasites (e. g. ich, etc. ) and external fungal/bacterial/viral lesions (e. g. , fin rot). It is particularly useful in hospital and receiving tanks for new fish and whenever new fish are introduced to a community tank. DIRECTIONS: In the aquarium, use 5 mL (1 capful) to every 40 L (10 gallons). Repeat daily as required as long as fish show no stress. For 1 hour dips, use 3 mL per 4 L (1 gallon). Dips may be extended if fish show no evidence of stress. In case of eye exposure, promptly and thoroughly wash eyes with water and seek medical attention.