Hi Ponders! This is the first place I've found anything about hyacinth so I'm giving it a go! I'm a new ponder (and a new AP chatter) trying to figure out what's killing my hyacinth. I've had my water tested - potassium, PH, nitrate and nitrite are all good. Other plants including hibiscus, arrowhead, water lettuce and two things i can't remember are all doing well. I have a problem with string algae but keep it in check cleaning it by out by hand. Fish (only 7) are thriving. Pond is about 3,000 Gs and I live in Sacramento, California. Any thoughts? My only observation is that we did have one night of rain followed by several hot days and that sometimes the hyacinth gets sprinkled when the lawn is being watered - maybe it got burned? The plants look yellow or brown and dry. some leaves and the air bubble things are dark brown and squishy.