Q: What is the difference between Alkaline Regulator and Alkaline Buffer?
A: The difference is that Alkaline Buffer is a carbonate/bicarbonate based buffer and Alkaline Regulator is a phosphate based buffer. High phosphate levels can promote algae growth so it is often a better choice to use a phosphate free buffer like Alkaline Buffer. The only drawback to a non-phosphate buffer is that there tends to be more pH fluctuation owing to CO2 equilibrium. Phosphate buffers lock the pH in quite well and hold it there.
Q: I try to keep my water between 6.8 and 7.2 pH so I'm not aiming for a perfect 7.0. Why wouldn't I use your Neutral Regulator instead of your alkaline products?
A: You certainly can use Neutral Regulator if you're trying to get to around 7. Alkaline Buffer and Alkaline Regulator are indicated for use if you are trying to get a pH above 7.