I have the Taylor FAS-DPD test where you use the powder and titrating agent but refills are hard to get and very expensive here in Canada. I have an SWCG and normally I don't have issues as I keep my CYA around 60 and my FC around 3-4.
My understanding is that one of the benefits of FAS-DPD is the accuracy at high FC levels. Since that isn't really an issue for me unless I have to SLAM, which I have never had to do, can I just use an OTO test or the basic DPD test daily such as is contained in the K-1001 kits. I can buy the reagents at a local store for much cheaper. And I can use the FAS-DPD tests once a week just to be sure, or if I have other problems.
FYI - the cost to just buy some FAS-DPD powder and titrating reagent including shipping and tax is about C$70.