Some tropical fish prefer warm Waters plus high uneven temperatures. There are other fish that like much colder uneven temperatures to survive! When the water chiller in our fish tank quit working, I went online to find a new one. For less than $200, I was able to find a water chiller for the tank. The water cooled chiller is absolutely perfect for freshwater, seawater, or even a gas tank. The water chiller is made from ABS material that will not rust. There is a temperature display screen on the front of the water chiller. I decided to order the chiller online plus the item was shipped to me in less than 5 days. I was able to get the water chiller, a submersible pump, the power supply, plus a hose… All of the parts necessary to install the water chiller were inside of the box along with simple study guidelines. It took roughly an hour to install the new watercooler, however it works beautifully. The fish have more energy plus they no longer seem to be lethargic plus listless. I have been thinking about adding another fish tank to our household. I would honestly like to have a tank with box jellyfish. Box jellyfish are actually one of the most dangerous creatures in the sea plus the smallest sting can paralyze plus kill an adult human. I think that box jellyfish are entirely interesting plus that is one of the reasons why I think they would make a great addition to our household aquarium! Regrettably, they are extremely costly plus undoubtedly dangerous. You need a special license just to obtain the sea pet.