shells will buffer the acidic water to about 7-7.2. You are correct.
The nitrification process as your system matures will naturally lower the ph.
personally...I do not think I would worry too much about it at this point.
I dont think the fish death was caused by a ph issue...
Just my opinion
Put all excuses aside and remember this: YOU are capable - Zig Ziglar
Well, things are going well...no more floaters. I'm going to keep only the "Pipe Siphon by Apollo" post updated. To all that want to veiw my set up or follow my story line, I hope you'll join me there .
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I HAVE NOT FAILED. I'VE JUST FOUND 10,000 WAYS THAT WON'T WORK. Thomas A Edison