What is the shelf life for Fleets (phosphate)?

I can't say for Fleet specifically, but having worked in a chemical factory, all chemicals degrade over time. Generally the expiry dates on the bottle are acurate. There's a reason they put them on there. For the price of them, if you've got some that have expired, chuck 'em in the trash and get new ones.
 
How much are you using Scott?
I remember, way back before I learned how much PO4 dosing was right for my pruposes, having bottle of Fleets for 8 months to a year. I don't think you'd lose much potency within a year and the stuff is so cheap, I'd replace it at that point if there was still some remaining.
I've been using 5 - 6 bottles a year (sometimes more) for quite a while so this is a moot point in my case.
I buy the 'economy two pack' and I think that they feel like I've got some serious problems at my pharmacy:). I get some strange looks.

Len
 
buy the 'economy two pack' and I think that they feel like I've got some serious problems at my pharmacy. I get some strange looks.

That is great!
I have probably used just a little over a bottle in a year! Maybe I am underdosing. Lately, with my usual dosing, I have struggled to achieve .25 ppm. I am increasing the dose now. My plant mass has increased but I don't think I have compensated appropriately! Maybe I will chance some odd looks from the pharmacy today and get some new fleets!

Scott
 
Test it frequently and add drops as needed for the proper N/P ratio. It's important!
You will see better growth and probably less glass algae, etc.
BTW, yes I looked at your tank and it's definitely changed in mass.....very nice.:)

Len
 
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