After a little online research, I decided to buy mopane driftwood for my Fluval 2.6 gallon Spec III aquarium. I have extremely hard water,so I was not adverse to adding an element to my tank that could potentially lower the pH, in addition to the potential aesthetics of the piece. I couldn't be happier with my purchase. I knew that my purchase would probably not look anything like the pictured piece, but I am not dissatisfied - indeed, I am very happy with the look of the driftwood I received. It is a hardwood and doesn't float, so you won't need to anchor it at all. The mopane wood is two-toned, with a very light tone and a black tone. It looks unusual and beautiful. If you plan to purchase mopane driftwood, you will have to do a bit of prep work if you don't wish to turn your aquarium water into a tea color, as the mopane wood will leach into your water. This is what I did to prevent my aquarium water from looking, quite literally, like tea. First, I soaked my wood for a few hours in tap water, using my 5 quart Corningware Dutch oven. I emptied the dark brown water and replaced it with fresh tap water, and then I commenced to boiling the driftwood. After heating the water to boiling, I turned off the burner and let the wood soak for 3 hours in my Dutch oven, with the lid on. After soaking for 3 hours, I emptied the dark brown water, filled the Dutch oven with fresh tap water, and heated the water to boiling again. Once the water was boiling, I again turned off the heat and let the mopane wood soak for 3 hours before dumping that water and repeating the same steps again. I did this repeatedly for the next 48 hours, until the wood was only lightly staining the water brown. Because I was using my Corningware Dutch oven with the lid on, it retained most of the heat during each 3 hour soak without requiring me to leave the burner on. This was important to me because the hot water enabled the wood to leach more quickly, and I didn't want to soften or otherwise damage the wood by leaving it over a constant flame. Also, if I was sleeping and didn't wake up for a water change, I didn't have to worry about boiling the pot empty and starting a fire. As it was, the 3 hour soaks were perfect - the water was still so hot that I couldn't touch the wood or water even after 3 hours. After constant soaking in hot water for two days, my driftwood was now a uniform dark hue. I worried I had ruined it. I left it to soak in tap water at room temperature while I sat up my aquarium. To my relief, once it was out of the hot water for a while, it returned to its natural hues. My aquarium has been up and running for a few weeks now. It has live plants, and last week I finally added the fish. I believe the mopane wood has helped to lower the pH, but even if it hasn't, it looks great in my tank. My water is clear, but when I perform my weekly water change, I can see a light brown tint to the discarded water. This is acceptable to me, because my water stays clean and clear, despite the tint. I highly recommend this driftwood and I would buy it again. However, if you aren't willing to put in a lot of prep time soaking the wood, be aware that it will turn your aquarium water the color of tea.
