Reborn is the calcium reactor media I use for my 400g reef. It's clean, nice and coarse and is ready to use right out of the bag.
This is a 4 kilogram bag (8.8 lbs) of media, which is a little more than most medium-sized calcium reactors could hold... so you'll have extra to top off with later. Buying in bulk saves money.
The Two Little Fishies ReBorn is a coarse aragonite calcium reactor media made up of completely dissolvable fossil skeletons of reef building corals from the Western Pacific. ReBorn is designed to replenish calcium and carbonate alkalinity, strontium as well as trace elements to bring your aquarium back to its normal state, making you and your fish happy for a healthy and successful aquarium.
Type in stock: Large grade. (April 2021: this product is a little smaller now, and the media is darker, as pictured)