Dichlor/bleach method - combined chlorine?

[Bouncycow]

Hi all - apologies for the possibly dumb question but I'm trying to get going with the dichlor/bleach method.
Am I right in thinking that just before a soak free chlorine should be present, say 1-3ppm, and combined chlorine should be zero?

At the moment I have varying levels of free chlorine but I always have some combined chlorine, say 0.4 - 0.8pmm. If it should be zero, should I be adding more bleach after a soak, or should I be adding MPS instead?
Thanks

[waterbear]

Many spas never get CC below .5 ppm As long as it's below 1 ppm you should be good. Before using MPS I would try running your FC a5 3-5 ppm. What is your CYA?

[Bouncycow]

Thanks! 
CYA is a bit high, about 45 I think: I find the Taylor test a bit subjective. Some days it looks like 50 but the next day it’s 40. I must have overshot a bit: I didn’t have the Taylor kit then. On the next drain and refill I’ll aim lower…

[waterbear]

do the CYA test outdoors in open shade and hold the view tube at waist level. This will help insure better repeatability. The test is somewhat subjective.

With CYA in the 40 -50 ppm range run your FC at 4-6 ppm. This should take care of your CC issue, FC in the 1-3 ppm range is fine for water with no CYA but once it's introduced you need to run it higher for the same sanitizing and oxidizing activity. with CYA at 30 ppm you would want to run it at 3-5 ppm.

[Bouncycow]

Excellent, thanks: I'll give that a try. Much appreciated