umm i have a managuense and i asked one of the workers how to harden the water a bit, he recommended buffers or crushed coral he told me how wen they get jaguars in they put them in the african system were the waters hard. i went with the crushed coral. a little wile later one of the other workers told me i shouldnt harden the water for my jag cuz soft is better , he also said crushed coral can cause algae blooms. does anyone know about this stuff?