Hey all, I am new here at TPT. I wanted to tell you about a recent experience with petrified wood. I ask that you let me know if you had similar experiences. This is about a tank that was newly set up and used petrified wood for decorative/retaining level purposes. Lots of plants, lots of light, onyx substrate, cool driftwood. Shortly after setup, everything was covered with a thick blanket of algae. We got all varieties of algae eaters. They did a great job, then the water turned green. Soupy green. The pH went up. We did water changes - lots of them. Got frustrated. Did bigger water changes. The pH fluctuated so much that the water changes started killing the fish. We thought there must be phosphate in the tap water. So, we added phosphate remover. That did not work. We turned the lights out and threw a blanket over for four days. That did not work. Finally we got the bright idea to get a phosphate test kit. From a scale of 1-10 with dark blue being 10. It tested more blue than the test could indicate. The tap water tested between one and 2. WHERE was it coming from?? The substrate? The driftwood? NO!! It was the petrified wood!! There was a white substance on it that I could scrape off with my fingernail. I said let's test this for phosphate. With our handy screwdriver, we scraped off a bunch into the nice test tube. Added the sulfuric acid (part 1) of the test. It immediatly began to bubble. We added part 2 of the test. It came up an 8 or so.
I have an old book with pictures and descriptions of minerals. There are different groupings of minerals. (i.e. quartz, amethyst fall under silicates). Well guess who's pretty picture falls under the grouping of phosphates? That's right. PETRIFIED WOOD. Well, long story short, the rock is gone and so is our phosphate/algae problem - for now.
Beware people. Depending on what part of the world this stuff comes from. This is an unsuspecting piece of rock that was sold to us from a fish store. We did not even think that it could be the culprit since it did come from a fish store. That was our biggest mistake.
Thanks for reading my rant. I look forward to hearing your horror stories too.