Beneficial Bacteria Survival?

[ShanerBock888]

If the room temp was 60 F, then that's a good thing as it lowered the BB metabolism. Keeping the gravel submerged was good as well. (The rest of course was not so good.) Anything that dried out is basically useless. BB do not create spores and have no adequate mechanism (as some bacteria) to withstand desiccation.

I'd carefully scoop up just the top 1/2 inch or so of the gravel and use FreshyFresh's suggestion. (Place the bag in the filter if possible.) It can't hurt your effort and it might help the tank startup faster.

Yeah I understand that the 6 days wasn't ideal, but it's a lot of work setting up a 300 gallon tank. I was unable to take the ideal route and put the gravel directly into a functioning sump. Nothing dried out, I kept it submerged intentionally, it's just that I had less spare time than expected and the 2-3 day gap turned into a 6 day gap