Hi Im testing out a Hydro setup, and it got me thinking, since I've already put my lovely seedlings into their first rockwool cube, Is it okay to use the first same water you soak the bigger rockwool cubes into for the next stage? I noticed how it changed my low-nute & pH adjusted OS water quite alot, and since its my first time trying out hydroponics im confused, if I should just soak them all in tap water and dont mind the high EC, or use/waste Osmosis water?