ThriveCaps | Premium Root Zone Fertilizer Capsules | 60 Tabs New and Improved: ThriveCaps are a very similar product to the previous ThriveTabs, with a few improvements. These capsules dont require any additives to make them stick together which allows them to be smaller and more concentrated while still delivering similar nutrient levels. Another improvement has to do with ThriveTabs causing clouding in some tanks. I changed the formula a bit to reduce this. I had a few people who had clouding issues with ThriveTabs try ThriveCaps. None of them had the same clouding issues!!!! ThriveCaps - Substrate additive for planted aquarium Contain Micro and macro elements as well as other minerals ThriveCaps are nutrient rich capsules which are intended to be placed in the substrate of a planted freshwater aquarium. They will provide a long lasting nutrient source essential for healthy plant growth. ThrivedCaps are a blend of dry Thrive mix, iron rich clay and mineralized top soil. How To Use? Place a capsule at the base of each plant or space out around the tank every 5-6" in a grid pattern. Push down to the bottom of the substrate as far as you can. Replace every 3-4 months or as needed.