AAP SeaLab Blocks
Small 42 gram (.042 kg) Sea-Lab (for 20-50 gallon marine aquariums)
1 KG Sea-Lab Block (for 1000 gallon plus ponds or aquarium systems)
SeaLab Blocks are a professionally proven and simple way to maintain trace elements as well as calcium in marine aquariums dating back to the early 1980s.
Sealab can also be used for high mineral/pH/alkalinity freshwater use, but for community freshwater aquariums, especially Amazon/Betta biotopes, the Sealab should NOT be used!