ph drop after large water change?

Nah i had to order a kit to test kh and it wont be here for another 3-5days. Im gonna put the granite in there tomorrow and see if it helps. I went to the lfs to get some crushed coral, but the guy that worked there talked me into getting Seachems Neutral Regulator. He said itll take it to 7.0 every time and isnt harmful to fish or plants...but im still sorta skeptical. Anybody tried this stuff before?
 
I would have gone with the crushed coral.
 
Yea as soon as i left the store i thought d@mn i shouldve gotten the crushed coral. I hate putting any chemicals into my tank, but this dude was a good salesman. The fact that its made by Seachem helped my decision too. Ive used a ton of their products before with great success. However, im still gonna try some "natural" remedies before i go with that. Im going to Petsmart to get some crushed coral because the lfs only had 25lb bags, and im gonna put in some good ole' North Carolina quarry granite later today. Anything else i can do to raise ph?
 
Actually, most granite and many other igneous rocks will raise and help stabilize ph/kh. If using granite you should find the darkest stone possible(NC Granite is usually extremely dark) as its higher in carbonates, which ill raise your ph. I always use the "drop-fizz" method for finding rocks that will raise ph. Just place a couple drops of hydrochloric acid(from a nitrate test kit) or vinegar on the rock...if it fizzes it will raise the ph. Im hoping that the granite and crushed coral will raise my ph and stabilize it at or around 7.0.
 
Heres a little update on the situation. Ive had the granite and cruched coral in there for three days and my ph is now at 6.8. I didnt think it would come up that fast, but im glad it is. Its not rising as fast as it was the day after i put it in so its probably about to stabilize. If its at 6.8 ill be able to finally add my co2, and if it drops too much ill add more cc.
 
Yea i was surprised with the results. Today has definitely been a good day as far as my fishtank is concerned!
 
Ok so my kh test kit finally got here, which means ill probably be adding my c02 either today or some time this weekend. My ph is still holding steady at 6.8 and my kh is at 40ppm. What should my target kh number be?
 
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