Well it's a dirted 29 gallon tank with crushed pebbles over the dirt. It's been up for about 2 months now. Cycled empty through the nitrite spike and then once everything leveled off at the 2 week mark, i added lots of plants and some platys and let it continue to cycle. But the ph levels had been dropping since I started the tank and when it got down to 5 I added the crushed coral. Over a few days period, I added about 6 measuring cups of crushed coral and that brought the ph up to a 7. Everything seemed fine for a few weeks after that and then my alkalinity started creeping up and now it's so high my test strips don't measure it even semi accurately. I did a %50 water change and the alkalinity dropped for 3 or 4 days and went back up again. Even so, all the fish seem to be happy and thriving. I've since removed the platys and replace them with skirted tetras and a gourami. My water tests show no nitrite, very little nitrate, no chlorine, hard, very high alkalinity, and a ph level of 7.
Does this help? I realize the tests strips aren't very accurate but I don't have a huge wallet to spend on water tests at the moment.