I used to harden my goldfish tank with a bag of crushed coral in the filter. I had a great system that took me weeks to perfect, and it worked just how I wanted it to. I went away on vacation a few weeks ago and had someone else do my water changes. They didn't follow directions and emptied my bag of crushed coral to refill it with new coral. Now I haven't been able to get my tank back to where it was. I don't know what I did so right or am doing so wrong, so I'm going to change my methods. I'd like to try a substrate of crushed coral sand.
What sand should I use? I see a bunch of marine sands out there, but I'm not sure which ones will actually raise the GH, KH, and pH. I'd also like to find a soft sand as these are goldfish and spend a lot of time sifting through it.
What sand should I use? I see a bunch of marine sands out there, but I'm not sure which ones will actually raise the GH, KH, and pH. I'd also like to find a soft sand as these are goldfish and spend a lot of time sifting through it.