Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Ruined the Aquarium Environment

These feeding blocks ruined my classroom aquarium's environment. We had a total of 10 days of spring break vacation. When I got back, the floor of the aquarium and all the plants were covered with a white debris, the water was clouded, and one fish who was visibly struggling to breath died a few days later. It took a huge amount of effort to restore the aquarium's healthy environment. I will never again use a feeding block for an extended period of time. My students and I were deeply saddened by the state of the aquarium upon our return. In the future, I will shell out the big bucks for an electric fish feeder.