Do Unused Fert Tabs go Bad

[aquarius]

I have some Wondergrow fert tabs which i bought a few yrs back. Recently i went to open it and noticed that the colour is a little darker than when i first bought it and when i break it up into halves, it was also much easier - when new it was very difficult to break it up.

I know that ferka tabs cannot be used once it doesn't look good. I would like to know whether can i still use the Wondergrow tabs cause i'm afraid that the bonding agents used to bind the chemicals to make the tab will be toxic to the faunas.

[barmby]

I think no problem. Personally, I am not very particular. Therefore, I will use it if I were you.

[aquarius]

Thanks for the input. Hope others can share their experience especially those that have bad experiences with tabs that are kept too long.