# Sand turns Black?



## elbmek (May 4, 2017)

I found the old thread via google, so here I am. I have just posted a long detailed post on what was later described as 'an old thread' and it not only recommended I use a new thread, but deleted all my work. Try again ....................

I had a tank that had good sand in it for a very long time, plants thrived, fish healthy and a few snails too, but everything was great. Then the course sand began to blacken, if I stirred it up, bubbles rose from the substrate and it 'stank'.

I stripped the 48 inch tank, threw out all plants and bogwood and put finer new sand in the tank, set it up, new plants new bogwood and all was fine until about 2 weeks ago when I noted a few black bits. Today the black is back with a vengeance, I stirred up the sand, no bubbles and no smell but this cannot be right surely. In all my years of keeping trops, never had this problem before. I thought it might have been some bottom feeder pellet food, so stopped that, obviously I was wrong! This setup has not seen the pellet food. I feed my fish on Aquarian and occasional blood worm (frozen) but only about 3 times a month.

I dont overfeed, in fact the opposite, I leave them unfed about twice a week. I have normal community fish and a mini plec, two clown loaches (still small) and a few corys. 1 large angel. It cant be normal. I am very tempted to drop the whole project.

The image shows some upturned sand, ignore the line across the image, its a tape mark on glass.


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