AQUARIUM IS SALTWATER READY BUT WILL ALSO ACCOMMODATE FRESHWATER. BUILT IN SUMP IS HIDDEN IN THE BACK OF THE ADJUSTABLE OVERFLOWS WHERE THE RETURN PUMP IS LOCATED. I PURCHASED A SMART PROGRAMING HIGH OUTPUT LIGHT FOR HARD AND SOFT CORALS THAT CAN BE PROGRAMMED TO MIMIC THE SUN, WHICH FEATURE THE MOON WITH MOONLIGHT ALSO. THIS IS A BEAUTIFUL AQUARIUM BUT I JUST DO NOT HAVE THE TIME TO CARE FOR IT ANYMORE. IT WILL COME WITH A HEATER, MAGNETIC GLASS CLEANER, AND ABOUT 40LB OF ROCK THAT LOOKS LIKE SALTWATER LIVE ROCK, THE ROCK CAN BE BROKEN DOWN TO THE SIZE YOU WANT IT. AQUARIUM WAS $300- EXTRA LIGHT $150 $450 VALUE- ASKING $250 Aquarium Specifications: Total Volume - 20 Gallons Dimensions - 23.62" L x 15" W x 13" H Glass Type - Low Iron Glass Thickness - 6mm Pump Specifications: Max Flow - 326 GPH Max Head - 5 FT Dimensions - 3.7" L x 2.5" W x 3.4" H Output Size - 1/2", 5/8", 3/4" barbed Input Size - 1/2", 5/8", 3/4" barbed Power Consumption - 15w @ 24VDC Powerful Return Pump Spacious Filtration Chambers Great for Small Soft or LPS corals Ideal Clownfish & Anemone tank LIGHT SPECIFICATIONS: Offer built-in timer Maximum 24 time points programmable,save external timer,both attractive and practical Offer smart control system Supporting three control modes,easy program sunlight/sunrise/sunset/moonlight Six channels control of color and intensity,adjustable spectrum output Unique design Ultra Slim&noble body thickness:0.47"(23.5mm) | Smart fans and smart temperature control system | 3 in one lens with 97% transmittance,107 degree secondary optical lens | Energy-efficient 5W 3535 LEDs & XPE LEDs | Adjustable Hanging kits