Pufferpunk
New member
Yes, if he has no fish it shouldn't hurt anything to release the toxic gas. Otherwise, he might just want to siphon out the sand & start over with seeded sand.
Get a cup of sand from their refugium.
I'm now just chiming back in... that you really didn't take the advice of some of the more senior members on this board and that was just patience. You're tank is cycling. leave it be for it's cycle. It's going to do everything short of throwing up on your floor until it is established.