I accidentally added an unknown solution to the gel and it got stained in a minute with proper bands. It is not iodine or ki mixture. I suppose it is either a staining solution from Folin-Lowry or silver staining.
In zymograpgy, the plase of bands is not stained and being cleared. If the whole of your gel is colorful and this colur can not clear by destaining, you must run zymogram again.
The silver nitrate dye is very stable and not cleared. Follin lowry dye is protein specific and only the place of the band must be colured.