Heater use for reef aquariums.

Never let the last inch of the top of your heater touch the aquariums water, they say they are completely submersible, but they are not!!!

Only place the tube part of the heater in your water, leave the top half inch and controler dial above water always!

Never turn on heaters out of the water, if this happens, turn of the electricity to it and leave it somewhere safe until it cools.

Never put a heater into water when it is hot, that will crack the glass tube and electrocute you or your fish.

Heater power leads tend to run quite warm and the plastic over time will become brittle, be careful to not bend and old heater power lead or it will develop cracks and become live and be dangerous!

If possible use the heater in external filtration-sump areas, its safer in the long term there.