I would recommend trying 4 part RO to 1 part tap. If my math is correct that should get you close to a GH of 10. Tap water hardness can very from place to place and it is possible the water at the fish store is not as hard as yours. Also somme fish do well in hard tap water while others do not. so with a GH of 38 there might be very few fish available that can handle your high GH. With a GH of 10 you would have a lot more choices. I would also recommend you look on line for a water quality report for your area. That might have more information on what is in your water. Then post a link to the report.
You can mix 4 part ro and 1 part tap in a small container and then verify the GH and KH with a test kit. Also I would recommend using thrive fertilizer with the mixed water to insure it has all the nutrients plants need.
Thank you for your help!
So are you saying that the lfs are using softer water? I have read that if fish are born and raised in tap water, however hard it is, they get used to it. Isn't it possible that the fish and plants in lfs are already used to 38 dGH water?
Also I mixed 1 tap with 2 ro and it has about 12 dGH and 10 dKH, kinda sounds ideal. (Wouldn't 1:4 ratio give me a GH of 38ų5=7.6?)
Last edited by somewhatshocked; 08-07-2019 at 01:59 PM.
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