A pond thermometer is a must for every watergarden. Monitoring the water temperature is very important thing to do especially in the spring and fall. When water temperatures are below 55 degrees, you should stop feeding your fish. This pond thermometer can float or sink. It is made of very durable hard plastic. PT1 ponddepot@msn.com Copyright - All World Rights Reserved Pond pumps, Pond Kits and Pondless Waterfall kits, Underwater Pond Lights. Aquaclearer Extreme bacteria and String Algae Buster and pond fish food. Pond Depot provides Do-it-yourself pond kits and Pondless waterfall kits delivered right to your home at great prices! Thank you for shopping at Pond Depot you online pond superstore!