red stuff on sand, small "bubbles" on rocks

[parkinsn]

Sounds like cyano to me. I would stop dosing CV and SP, just use the CS and Bak. You can also mix CS, Bak and Zeo Zyme together, be sure to shut off your skimmer for 3 hours or so when doing this. Do about 700ml of tank water for the mix and let it sit for 8 hours before you dose it. Then slowly ramp up the SP, see what happens, then slowly start CV again (just cuz the dosage says 1 drop per 25g doesnt mean thats what you should do) Have a look at lobster boys thread and look at what he doses.