Dry salts and humidity

[cctt]

Some of my various dry nutrients have been exposed to humid (70-90% RH) air and as a result I'm worried that some of them may be deliquescent enough to have absorbed water. The CaNO3 gave me the first clue -- leave a pellet of it out in front of a swamp cooler and there will be a droplet in its place later. As I weigh out these salts to use them, any additional water content will throw off my measurements and elemental ppms in solution.
So, farmers, a few questions for you:

• Which salts do I need to worry about? Aside from CaNO3 that is.
• Can I easily purge excess water in an oven? Suggested temperature/times?
• I've been to a few stores looking at plastic totes in the 3-5 gallon range - none seem to have an air-tight seal. Do any specific products come to mind for this purpose?

 

[baba G]

Paint buckets and there corresponding lids have a nice seal, not sure on air tight but seems so.

 

[Seamaiden]

What about getting some of those desiccation packs, cctt? I can't answer any of your other questions, I really don't know, but I'm thinking that if you used what manufacturers overseas use for those products that end up on a boat then you'd be golden and wouldn't have to be so worried.

Otherwise, the pet food totes are supposed to be sealed and air-tight.

 

[SmokinDogCujo]

When I started using Jacks Hydro and CalNit I purchased the 25 lb bags, which was way too much! I use the quart size canning jars to store the salts in for my weekly rez changes. The CalNit is in a 5 gallon container that has a rubber seal inside the lid. Don't know how airtight it is but I've had no issues with excessive moisture and the humidity in my area is always high. The bucket originally contained worm castings, but it seems to be a repurposed 5 gallon paint bucket.

I'm pretty sure the CalNit is the only one you have to worry about when it comes to moisture.

Don't know about the oven