Not with Aragonite.
And if you take the appropriate steps to ensure accurate dosages with say, Epsom salt and Baking soda, there will be no fluctuations in anything and Consistency will prevail. Kh will do nothing but help and that fluctuating a bit is not going to affect anything except the stability of the water during times of Ammonia spikes. Carbonates and Bi-Carbonates do one thing. They absorb harmful acids to protect the Ph balance in the water from changing.
I'm going to hold off on adding sand because I've did such a big water change I want the sand and texas holy rock to catch up and see if the KH comes up on its own. A side note for those that use the API test kits. When you compare the tube color with the the card to see what the test results are, do you lay the tube on the white part of the card or stand the tube on the card. I've seen both ways.
