REMARKABLE PERFORMANCE! Accubrate calibration solution is specifically formulated to calibrate refractometers to accurately measure the salinity of saltwater, reef aquariums as well as natural seawater. | ACCURATE RESULTS! Our calibration solution is formulated from a high purity blend of salts to produce accurate readings every time. Refractometers must be calibrated often to obtain accurate readings. Note: RO/DI water will not calibrate your refractometer correctly. Always use Accubrate to ensure correct salinity readings - your aquatic friends will love you. | EASY TO USE: Our specially designed bottle has a built-in dropper tip which eliminates the need for a pipette. Simply squeeze a few drops of Accubrate directly from the bottle onto the refractometer’s prism slide and you are ready to calibrate your instrument. (Drops come out at a very controllable rate.) | LONG-LASTING: You need just 2 to 3 drops of our calibration solution to calibrate a refractometer. Using a few drops means our 60 ml bottle should last a very long time. For best results calibrate refractometer often to ensure accurate readings.

OUTSTANDING FILTRATION! Each bio ball is covered in spines to dramatically increase the surface area of each ball providing space for a massive number of beneficial bacteria to colonize. These good bacteria break down harmful organic waste. You will receive approximately 125 1-inch bio balls with no mesh bag. Just rinse and use | SUPERIOR BIO MEDIA: A huge problem with other bio balls is that they have a sponge in their centers to increase surface area, but sponge pores trap gunk that does not wash away. This trapped gunk reduces water quality. This problem is solved with our bio balls! How? They have a small solid center covered in spines that won’t trap gunk. You never have to suffer with poor water quality. | TOUGH AND UNIQUE! Our bio balls’ spherical shape and precise spine placement permits them to pack tightly into any shape or filter type without losing surface area. Molded from high density plastic, these balls are lightweight but tough enough to keep their shape and will never degrade or wear out. Bio balls can be used loose or in the mesh bag with plastic zipper. | TRUSTED! Our Bio balls are 100% polypropylene making them reliable biological filtration media for fresh and saltwater. They are manufactured for use in koi ponds, freshwater fish tanks, saltwater aquariums, aquaponics, fish hatcheries and much more. These 1” bio balls are perfect for the limited space of an aquarium sump. | EASY TO CLEAN - If organic waste builds up in the bio balls, they can be gently rinsed in dechlorinated water to remove debris and refresh the bio balls. Use our FilterFirst, dual density bonded filter pad, or water polishing pad to capture large particles to help keep your bio balls clean of debris.