Keeping light, Co2, temperature, KH and GH constant, I notice stunted tips on my guinea if I neglect to dose macros for a few days. If I get back on dosing routine, they begin growing very quickly. Missing a dose has a noticeable effect but they spring back very well.

My GH is 6 and my KH is 5, reconstituted RO water. 3 x 13w over 2.5g. Aquasoil. Dunno the Co2 levels but I'm blasting pressurized Co2 from a nano diffuser with a 40 gph water pump and the HC pearls well so I know the Co2 is up there.