I've had considerable trouble keeping the undergravel cable heater in my 55-gallon freshwater planted aquarium buried beneath the gravel. Whenever I move a plant in the aquarium, the cable pulls out of the substrate because it seems that the plant roots have taken hold of the cable. Is there anything I can do to keep the cables beneath the gravel?
Undergravel cable heaters are often used in freshwater planted aquariums to promote plant growth. To keep the cable heater below the substrate, cover the cable with a plastic or fiberglass screen before you add substrate. This procedure is best performed when initially setting up your aquarium. When selecting a screen, be sure it is made of a material that will not degrade or inhibit water flow (do not use metal screen or screen with an extremely fine mesh). Use small plastic zip ties to tie the screen to the cable. Suction cups attached to the cable and applied to the bottom of the aquarium will ensure that both the screen and cable stay in place. In addition to keeping the cable heater in place, the screen cover helps anchor plant roots and prevents accidental uprooting by fish, routine maintenance, or aquascaping.