white grain when using salt

[7thheaven]

Hi all~

My salt becomes damp.
(I am not sure why but I think the bucket cover had problem)

When I used this salt for water change, I found there were some white grain in water. Not sure but I think it is from salt.

Do you know what it is? And could you tell me how to prevent from the damp?

Thanks in advance~

[bertoni]

Some calcium carbonate might have formed due to the exposure to water. The salt is probably okay, though. I'd fix the bucket cover problem. Some sort of dessicant might help, but salt mixes can contain a lot of water.

[7thheaven]

Thanks.

When Calcium Carbonate have formed, the KH , CA value are changed or maintained?

I use Seachem salt.

[bertoni]

The calcium carbonate formation will reduce the calcium and alkalinity levels in the salt. There might be other precipitates as well.