How big is your tank? If you were supposed to add 1 ml and you added 40 ml - you would need to change 98.5 percent of your water to get it to the desired amount. (1/40 = 2.5%). Tried to look up what was in that solution - but cant find it - unfortunately. Maybe carbon? Just saying lets say you did a 50% water change - it would be like you added 20 ml.
You could do a 50% change (would be like 20 ml), another 50% change (Would be like you added 10 ml) another 50% change (would be like you added 5 ml) another 50% change (would be like you added 2.5 ml) and another 50% change (would be like you added 1.25 ml). I just dont know how 'toxic' it is (or how much bacteria might be caused to grow, etc - most of these things have a margin of error.