Fish Treatments. Fish add color and life to your pond, and no one likes to see their fish become sick or unencumbered in any way. Aquascape offers a basic line of fish treatments that target most issues experienced by pond fish. Use our handy chart below to identify the problem, and treat with the corresponding product. It is important to treat immediately after noticing the first signs of fungus or a parasite problem on your pond fish. Fish Treatments. Common symptoms include white, green, or gray cottony looking patches, fish quickly rubbing or flashing against surfaces within the pond. Fish Treatments