Why purchase a separate and expensive auto top-off system when HYDROS can do the job for you? The HYDROS Auto Top-Off Kit comes with everything you need to use your HYDROS device (like the Control X2 or Control X4) as...

The HYDROS Control X4 PRO Pack includes two Control devices, the Control XP8 and Control X4. Combine these Controls to create a secure and impressive set-up for both saltwater and freshwater aquariums. Connect up to four sensor devices,...