do prime or biosafe ever "expire" after in water?

[gagaliya]

For example, lets say i do a 20 gallon water change but add enough biosafe or prime for 30 gallon. So now you have some extra dechlorinator in the water. If i wait say 10 days, and the water evaporates some and i top it off with tap water. Will those water be treated immediately by the left over biosafe / prime from 10 days ago?

basically do dechlorinators expire after some time in water? or do they always stay there like salt until used up.

 

[ddm0502]

I also have a question. I was going to start my own thread, but mine goes along very well with this one so I'll just ask it here. Will leftover Prime be removed with a carbon filter? So if you add more than neccessary, will the exess be removed? Or, if you're using Prime to detoxify a nitrite or nitrate spike, would it be removed by the carbon filter? Not having any problems with either at the moment but I'd like to know in case it ever comes up.

 

[dorkfish]

It should do it's job before being removed by carbon, wich is completely unessisarry by the way. I would add more dechloranator to the top off water, just to be on the safe side. The nitrite and amonia spikes should be detoxified by water changes, and NO chemical whatsoever should be relied on to detoxify these. Nitrate is a good indicator of DOC's and as said above, only water changes should be relied on to detoxify it.