Making the switch to RODI - The Planted Tank Forum
  • 2 Post By AbbeysDad
LinkBack Thread Tools Display Modes
post #1 of 4 (permalink) Old 07-29-2017, 06:49 AM Thread Starter
Algae Grower
PTrader: (0/0%)
Join Date: Apr 2014
Location: NW Suburbs of Chicago
Posts: 57
Making the switch to RODI

I'm almost finished setting up my new RO/DI system. In addition to using this water on a new tank I'm assembling, I'd like to convert my existing tanks to the new water.
I currently have two 20 gallon aquariums. The pH is 8.4 with a TDS ~700. I haven't quite nailed down the aged water chemistry yet, but I'm aiming for a pH around 6.5 - 7, GH 6 and KH 3.
I do weekly 50% PWCs on these tank. My uneducated plan is to just replace 1-2 gallons of tap water with the new remineralized water during the PWC and to just keep an eye on the pH until I get close enough to switch over completely. I say "uneducated plan" because I'm not basing it on anything... it just seems right in my head. I'm posting this thread in hopes of getting an educated opinion. Am I on the right track? I just pulled the 1-2 gallons number out of thin air. Is there a way of finding out the right/safe volume to mix in every week? It's been a while since high school chemistry class for me.
Coyne is offline  
Sponsored Links
post #2 of 4 (permalink) Old 07-29-2017, 01:54 PM
Planted Member
PTrader: (0/0%)
Join Date: Nov 2016
Posts: 234
A ph 8.4 and tds of 700?

I'm in Detroit and my ph is 7.2 and a tds of 125 out of the tap. I can go weeks on end with no water change and the highest I've seen my tds is 350.

I'm not real familiar with RO water though. I know anubias don't react well to it.
Wantsome99 is offline  
post #3 of 4 (permalink) Old 07-29-2017, 02:54 PM
Wannabe Guru
AbbeysDad's Avatar
PTrader: (0/0%)
Join Date: Apr 2016
Location: Central New York, USA
Posts: 1,360
I think I'd mix your tap water 50/50 with the new RO water (no additives) and test for TDS and gH/kH and see what you get. Then adjust as needed. Would seem a better approach than pure RO that you have to mess with minerals and pH.
Aqua99 and Aqua99 like this.

Tank On, Mike-
60g Marineland Community, Finnex Planted+ 24/7, Silica (pool filter) sand.
10g, 29g, & 37g fry grow out tanks, 110g stock tank.

What came first, the chicken or the egg. It was the egg, but not the egg from a chicken.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
AbbeysDad is offline  
post #4 of 4 (permalink) Old 07-29-2017, 05:15 PM
Planted Member
ustabefast's Avatar
PTrader: (0/0%)
Join Date: Jan 2017
Location: Santa Barbara
Posts: 210
I think that's a good conservative plan. I have similar liquid metal type water parameters out of the tap and I mix close to 95% RO (not RODI, which takes out everything), with tapwater and my parameters are around 100tds, neutral PH, KH around 4.
I don't have to add anything to the water because even after running it through the RO unit it still measures around 75ppm tds. So I just add in a small amount of tapwater to get the mineralization a bit higher.
ustabefast is offline  


Quick Reply

Register Now

In order to be able to post messages on the The Planted Tank Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome