Is It Actually Dolomite Gravel?

Unfortunately, I can't think of anything.

Vinegar doesn't always work as it's a weak acid (acetic acid).


Leaving some to stand in water should increase the pH slightly if it is dolomite - or even coral, aragonite etc. The way to be absolutely sure is to leave a second container with just water next to it and test that at the same time as the dolomite water. If the two waters stay the same, the gravel won't do anything for the tank but if the pH (and GH and KH) increase over a week compared to plain water it will help the tank.

A few moments ago I thought I'd test the jar of water that I put the supposed dolomite chips in four days ago, and it came out more basic. (A noticeable color difference.) So I tested the water in the control jar and it also came out more basic than the tank water, and more basic than the water with the dolomite chips. (Noticeably so.)  I emptied the test tubes, washed everything, and tried again. Same result.

So I had another bucket of water that has sat out for 24 hours and it's down just around 6-ish. Ok, pwew, as that's what went in at the last water change. Double-checked the tank, 6-ish. All is good there.

So I checked the tap water. Straight out of the tap tonight it's turning the testing solution green - well into the 7 range, which it's never done before. So the question - does tap water change Ph that much from day to day? Or an I losing my mind?

I'm going to take the chips out and rinse them off in the "6" water and then put them in a fresh jar of water, and leave a jar of the same water for control.  Maybe it's the light - I finally opened a window and held the test tube and the color chart out there, as it seems that all our "inside" lights are LED. It was still showing up like that, though. (The higher Ph in the tap, the "dolomite" and the control.)

Yeah, that threw me, too. They are both Mason canning jars. They had been previously used, so I thought perhaps they might not be clean, and I washed them out with very hot water and started over. I also rinsed the beejeezus out of the gravel. I also have a second sample of gravel from the same company, so I may set that one up today too, just for curiosity's sake.

I had known about the C02, but not about the anti-corrosives. It's just interesting that I could get two such wildly different readings 48 hours apart, out of the same tap at the same time of the evening, after having let the water run for a bit.  I am going to test it again in a few minutes, just to see if perhaps the light was playing tricks on my eyes.

I wash them in screaming hot water, and then let them air dry. Should I use the towels?

Hmmm. Well, I don't leave them sitting out. So it's not that. Haven't tested anything else again (been crazy busy today) but I'll check again in the morning. It could be that the gravel is just gravel and not doing anything at all.