Hello All- So after weeks and weeks of buying plant after plant.. only having everything turn to mush within a week.... it was brought to my attention by someone in a reputable aquarium store to test my water hardness. I went home and tested it... and I basically have no KH and low GH. the PH is currently at about 6.5-6.5 since adding new driftwood... previously it was a bit higher. Turns out NYC water is just seriously lacking in hardness. The GH in my tank is higher than the GH from the tap.. probably because I have some crushed coral in my filter. I have a betta fish.. who seems to be doing fine all along.. had him for 1.5 months. However I want live plants! I think I need to raise my water hardness.. KH and GH to make this happen I believe. I have been dosing Flourish Comprehensive.. but that's no help. What is the best way to do this? I had a limestone sand that.. when I previously had it in while cycling the tank.. raised my PH to the 8's. Which is too high I think... but if needed I can add a bit of that to raise my PH to 7 or 7.2 BUT... I've heard that rocks and natural things ONLY increase GH and not KH?? I've read baking soda to raise KH? is that safe?... how much and how often? I want my tank to be stable. But its only a 5 gallon.. so I do water changes once a week. While cycling (before I got the fish) my plants started doing more ok because I was hardly doing any water changes... and the crushed coral kept the PH high and stable. The issue with the coral is that it takes TOO long to work for such a small tank.. by the time it brings it up to where it needs to be.... a week has gone by and I'm due for another water change. I think I am better off with adding the sand.. which seems to counteract the driftwood quickly. But I don't know if this fixed my KH problem? Anyone know about this subject? There are a lot of seachem products out there... alkaline buffer... equilibrium... natural regulator? What should I go with? Plain ol' baking soda? How do I turn such soft water into something more stable in a 5 gallon tank? Thanks!!