Favorite copper plating bath recipe: Heat 250ml deionized water to 60*C in a 300ml beaker, stirring at 350 RPM Add 2.5g CuSO4*5H2O, wait until dissolved Add 4.6g EDTA disodium dihydrate, wait until dissolved Add 0.84ml of 1% Triton-X 100 solution in water Dissolve 5.8g NaOH in 30ml DI water, stir until clear, then add to bath Add 4ml Formaldehyde (37% HCHO) Lower stirring to 100 RPM and begin filtration with 0.5 micron syringe filter and peristaltic pump. No intentional oxygenation or bubbling. Filter return is below surface for minimal splashing.
I experimented a little with PEG and 2 2' Bipyridine, but didn't find them impactful enough to discuss in this video.