GH, KH, TDS and temperature all being close values ignore pH shifts and transfer the fish.
As long as the temperature is matched I routinely swap fish with a flip of the net between tanks with 5.9/6.2pH and 7.4/7.6pH.
Temps the same, the TDS is very close and fish don't care about pH differences in any experience I've had here. Shifts (rapid swings or changes) in GH, KH, TDS and the resultant osmotic pressure that's the yada yada that causes our critters issues not pH changes per say.
Tank looks like a great start.
The Fraternity of Dirt
If at first you don't succeed,,, keep kicking it
2-75g planted, 5-55g planted, 5-20g planted, 110g w/30g sump, 8-10g,
2012 update adding table top pleco pans & a 90g (Nutz)