Hi. I have a 10-gallon planted aquarium with gravel substrate and one bag of the Co-Op's crushed coral mixed into the gravel to help with keeping hard water and balancing pH. Just wondering if anyone has any suggestions on how long the crushed coral will last to have the desired effect on the water conditions? My tank has been operational for about 4 1/2 months, fish are 3 Dwarf Endlers. Can I add a little bit, say 1/4 of a bag of the crushed coral to raise my water hardness a little? It's a bit lower than it was 2 1/2 months ago and I just don't want to end up with problems for my fish. Any suggestions are greatly appreciated, thanks in advance 🙂