I purchased a 5 gallon of Armstrong Clark stain (black walnut). Before I purchased it, I used the calculator on your website to figure out how much stain we will need to cover our soft wood deck. The result was 4 gallon. For some reason, however, we only used less than 2\3 of this 5 gallon bucket. As recommended, we applied one coat only and followed the recommendation not to overapply. Now we are confused, why there is such a discrepancy between how much we used and the calculator recommendation? Were we supposed to do two coats? And most important, how should we store this stain now for it to last as long as possible? Again, it's an open 5 gallon bucket more than 2\3 full. Shall we leave it in the same bucket or better put it in some smaller containers? Where should we keep it - inside or outside? Outside would be preferred, of course, but we live in ontario with temperatures below 0 Celcius in winters. If we follow your recommendations, what is the longest possible storage life of this stain?
We will reply to your comment shortly· 06/12/2018See this about shelf life: https://www.armstrongclarkstain.com/articles/shelf-life-of-armstrong-clark-stain
2/3 of a 5-gallon pail means it is more than 3 gallons and that is why it rounds up to 4. So it is correct. In addition, coverage varies drastically based on the wood age and application procedure.