How concrete are reagent epiration dates?

[Nor'easter reefer]

Picked these up for 75$ a week or so back. Just getting ready to try them out and verify they work properly, and I noticed the phosphate tester reagent expired 11/2023. What are the odds that the expiration date is similar to most things nowadays and it's probably fine? Quite a decent chunk of reagents to throw away and plus, i want to try it and see if it works

 

[Nor'easter reefer]

 

[EeyoreIsMySpiritAnimal]

I doubt it's fine... buy new reagents.

 

[Nor'easter reefer]

I doubt it's fine... buy new reagents.

That's what I assumed but thought it was worth a shot.

 

[braaap]

If they didn’t get wet then I’m sure they are fine. I’ve had some 2-3 years expired. Compared them against brand new and got identical results.

 

[Nor'easter reefer]

If they didn’t get wet then I’m sure they are fine. I’ve had some 2-3 years expired. Compared them against brand new and got identical results.

I already ordered some new ones. When they arrive I'll compare a few and confirm as well.

 

[taricha]

I trust packets to hold up longer than liquid reagents generally, but I wouldn't be confident enough in the Ca, PO4, or NO3 stability past expiration to override my concern that I might just be wasting my time.

I already ordered some new ones. When they arrive I'll compare a few and confirm as well.

I am interested in these results though. Thanks!

 

[Waters]

I agree they are probably fine but the one time you test and get a result you aren't expecting (or wanting) you are going to question the reagents so they probably aren't worth using.

 

[gbroadbridge]

I agree they are probably fine but the one time you test and get a result you aren't expecting (or wanting) you are going to question the reagents so they probably aren't worth using.

But that can happen with brand new reagents too

Hanna nitrate has done that to me many times, phosphate not so much.

 

[Waters]

But that can happen with brand new reagents too

Hanna nitrate has done that to me many times, phosphate not so much.

I personally have never had to question new reagents but you are correct....it definitely can happen.....much more likely with expired ones though lol.

 

[Nor'easter reefer]

I am interested in these results though. Thanks!

 

[Dan_P]

Picked these up for 75$ a week or so back. Just getting ready to try them out and verify they work properly, and I noticed the phosphate tester reagent expired 11/2023. What are the odds that the expiration date is similar to most things nowadays and it's probably fine? Quite a decent chunk of reagents to throw away and plus, i want to try it and see if it works

Easy enough to check before throwing them out: compare their performance to new reagents.

 

[Dom]

That's what I assumed but thought it was worth a shot.

You could always double check the test with expired reagent to the new reagent.

 

[JayM]

Not very concrete. It’s very dependent on storage conditions. Reagents stored in high temps and/or high humidity may not be any good before the expiration date, stored cool and dry may be good long after.

 

[vetteguy53081]

Ive tested 3 month old packets with new ones and were almost a match. Hanna says refrigerating them buys extra life ( not sure if true but I am trying it)

 

[Miami Reef]

I predict the old reagents will test the same as the new ones. Please keep us updated. I’m very curious.

 

[Nor'easter reefer]

Ive tested 3 month old packets with new ones and were almost a match. Hanna says refrigerating them buys extra life ( not sure if true but I am trying it)

I didnt know that. I heard people claiming that keeping the reagent with the unit can cause issues? And that the vials should be stored with rodi water in them. Which I didn't know and was at first, very confused as to why the vials had water in them when I bought them used.

 

[Nor'easter reefer]

I predict the old reagents will test the same as the new ones. Please keep us updated. I’m very curious.

New ones just shipped today. Don't have a arrival date but I'll post results here when they come in

 

[vetteguy53081]

I didnt know that. I heard people claiming that keeping the reagent with the unit can cause issues? And that the vials should be stored with rodi water in them. Which I didn't know and was at first, very confused as to why the vials had water in them when I bought them used.

yes, the vials if scratched or dirty can give false readings.

 

[Nor'easter reefer]

yes, the vials if scratched or dirty can give false readings.

At least today wasn't a waste. I learned something it makes sense though.