Method wondering if my SN still good

[notsure04]

hi. I read ''only open your SN when needed'' I opened mine back in august last year.... I was sure I was going to ctb at the time. My sn bottle has been closed ever since but can I trust my sn will still work? Im scared it wont.
also I feel so shitty. I was to ctb last year, even mentioned in here and the fact im still here asking questions makes me a little embarrassed. But I had to get over it. I apologize if im asking something that has already been cleared before. I admit I've been lazy and really tired and thats why straight up asking about it makes more sense to me. thanks everyone for you time.

 

[Circles]

How long was it opened for?

 

[Chovyfan]

I would just get another one for a peace of mind. They're fairly cheap anyway.

 

[Lifeless mindset]

I recommend doing both aquarium + blood test to get some sort of idea on the quality of your sn

 

[Nolife62]

Don't know if you are still with us.
When they fill the bottles it is open to air, it's not vacuumed sealed. I think if was only opened for a few seconds it wouldn't make much difference