So, my current plan is to buy 25L of RO water when I can get to the lfs next week. I can’t really buy more at once as they charge for the containers. I’m not an adult so have to rely on my parents being able to take me. I can then use this to do a 50% water change with half RO and half tap water? Or would I be best only using half the RO water then half again so parameters don’t change too quickly? And I assume I’m best mixing the two waters together and dose the tap water with dechlorinator still. Sorry for all the questions, just want to make sure I get this right.