Mounds in sand, any ideas?

[Anonymous]

These two mounds have appeared in my sandbed they are quite big about an inch in diameter in one I can see at the top what looks like little hairs or bits of algae and also very long spindly stipey arms are coming out of the top (some kind of worm?) the other mound is right next to the first one but I can't see anything around the top of that one except for a kind of sausage shape curled on the top of the mound, these have just appeared over the last couple of weeks I was just worried that something sinister was going on under the sandbed ie noxious gases or something but the sandbed isn't that deep maybe the deepest bit being about 3/4 inch, there are plenty of worm shaped holes in the sandbed as if creatures are living in it in parts, is this a good sign, should I disturb the mounds or just leave them?

Any help appreciated

Carolyn

 

[Anonymous]

Sounds like spaghetti worms to me. Them and the other critters are a good thing.

You may want to consider deepening your sandbed. Current theory has it that with a sand bed of 4 inches or greater you develop hypoxic areas that support bacteria that turn nitrates into nitrogen and oxygen gas.

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