Nice! Very cool videos - love to watch them via this unique angle. Happy you're having good success with your larger WCs. My tank stays where I want it nitrite wise at 50% per week. I recently found ou that the city of PDX is raising their pH over time toward 8. My tank pH drops some because the water is also so soft, so I worry about doing larger than 50% due to potential shock. (Tap pH was always 7 before.)
clm08k - you discuss using plants in your tank which will help (roots) and you can use Malaysian Trumpet Snails to stir up the substrate for you.
I've read on planted forums that you should stick to a sand bed 1.5-2 inches to help prevent anaerobic issues.
Great research and plan of attack Mag for portland's city water. That a large ph increase. Wow! For us in Vancouver, WA. It's Well systems and about 7.6-7.8.
