Re: small seasonal pool--is it worth buying expensive test k
In my experience with an EasySet8 and an EasySet15, it was easier to dump and fill when it got bad. The issue with tiny pools is the margin for error is very small. The TF100 will allow you the precision you need to make accurate assessments and changes. The kit seems like overkill, but it is very effective. If you water is expensive, it ma be worth it in water savings. If your water is cheap... dump and fill.
When I add a few extra ounce of Cl to my 10,000 gallons, it not bad, but if you add an extra couple ounces to an easyset8, you have doubled the level. Also, solid chlorine adds so much CYA... so fast; it makes it impossible to stay clear, especially with the pump the pool comes with.
I have found my big pool is easier to mange than the sack pool was.