try to not let the lfs talk you into putting anymore chemicals into the tank before the cycle is complete. You will see various things that may happen: for sure your levels will spike, the ammonia, nitrite, and nitrates. You may or may not see a diatom bloom, this is a brown algae outbreak, usually caused by using tap water, but even without using tap water, it showed up in mine for about a week. Green algae, which can be controlled by a proper cleanup crew after the cycle is complete. A low or high pH, which usually will fix itself once the cycle is undergone or near its end. Some people use all sorts of chemicals in their tank, but chemicals only mask the problem temporarily. Naturally letting your tank run its course is in my opinion the best thing for the longevity of the tank. Keep your eye on the pH, because since you buffed it to get it higher and it's not even in its cycle yet, you may find that once it levels itself out it may be too high because of the buffer. Trial and error a lot of times in this hobby, that's why it's important to hear what's happened to other hobbyists.