My substrate is anoxic!... Every now and then, perhaps a few times a day, it lets out a little fart of hydrogen sulfide smelling gas. I'd heard that is poisonous, but my fish all seem perfectly fine and happy.
My tank has 2" of black flourite sand, and a fully planted substrate of dense planing. The tank has been set up for about 5 months now, and I had put in some Sera root tabs which I broke into quarters after I'd finished my planting. With a fully planted substrate, I hadn't planned to and can't readily do gravel vacuuming, but had been told that the plant's root would keep the substrate from getting anoxic.
Should I worry about these anoxic conditions? And should I do anything about it? My waterflow had been quite low previously, so I've substantially upped that but haven't seen yet whether that makes a difference. I'd heard Malaysian Trumpet Snails help, but would they disrupt my plant roots and dwarf hairgrass foreground carpet? And I've also heard people complaining about infestations of these, and I kind of hate snails anyway.