Remo nuts after they opened

Hello everybody as the title says i wonder if anyone knows how long i can use opened nutrient bottles for?

I ordered 10litre bottles of Remo nutrients and now its too late to sent back.

I read in remos website that they should be used within 6 months from when they are opened....

Do you think i can take them to 2 years because i have so much of them....?

I have bottled nutes that are over 2 years old and still fine. I have had others that weren't.....time will tell.
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