Red Sea 4 part program part 2 & Red Sea foundation B

[jalston6812]

Hey guys thank you in advance.. I currently use the Red Sea 4 part program but my part 2 (KH / ALKALINITY & PH STABILISER) has run out and the others are still pretty full..

Could I possibly run their other product (FOUNDATION B KH/ALKALINITY) until the other 3 parts are used up or are they completely different products and should just buy another lot?

Thank guys