Using bleach/liquid Chlorine is almost always a good thing because all it adds is chlorine, not adding CYA, calcium, or changing pH. Tabs are almost always Tri-Chlor tabs. If your pH is high and your CYA levels are low, Tri-chlor tabs can address both while eroding in a fairly constant flow of chlorine. Of course, if the pH gets too low and the CYA gets high or too high you have to stop. BUT if they are "dual-action" it means they have copper in them as well and do NOT suggest you use them.