That’s a four stage unit with a water saver kit added on. If you want to start fresh get the kit listed above as well as 2 ro filters and a booster kit. The water saver kit requires higher psi to operate properly (min 55psi)
RO Water
- Thread starter cccharliecc
- Start date
- Tagged users None
WWIII
2500 Club Member
I'd order the booster pump, sediment filter, carbon block and di resin. Then see how it does for you. To replace the 2 ro membranes you're looking at around $100 + and they may not be that bad. Then again, they may be! Can you tell what the tds is coming out of the ro membrane, before the di? Those water saver units definitely need higher psi
cccharliecc
Well-Known Member
ok, booster pump, and 4 stage replacement kit it is....may take time for the booster pump....I am curious to see if I change everything before I add the booster pump what the TDS will be.
VietExtender
Active Member
- Joined
- Jul 29, 2017
- Messages
- 187
- Reaction score
- 65
The booster doesn’t affect tds but helps with the amount of good vs bad water coming out. YouTube videos about rodi booster pumps and they’ll explain it better (from brs).
redfishbluefish
Stay Positive, Stay Productive
Staff member
Super Moderator
Reef Squad
Partner Member 2024
Excellence Award
Article Contributor
NJRC Member
Hospitality Award
I have an old 8800 where you purchased either the 1/4 inch or the 3/8 inch models. However, looking on Amazon, it appears the new models come as 1/4 or 3/8 by using reducing elbows. So either get a 1/4 inch model or one of these newer ones that could be set up as either..
Everyone is spot on the money here!! 
150ppm Tap Water after and RO membrane should be 15 ppm (or less) -
Then the DI Filter makes it Zero TDS.. you could use only DI and still get zero TDS, but it would be very inefficient way of doing so. (would cost much more)
1st Stage - Sediment filter
2nd Stage - Carbon Block
3rd Stage - RO membrane (looks like you have 2 on there)
4th Stage - DI filter.
that should help!!
150ppm Tap Water after and RO membrane should be 15 ppm (or less) -
Then the DI Filter makes it Zero TDS.. you could use only DI and still get zero TDS, but it would be very inefficient way of doing so. (would cost much more)
1st Stage - Sediment filter
2nd Stage - Carbon Block
3rd Stage - RO membrane (looks like you have 2 on there)
4th Stage - DI filter.
that should help!!
cccharliecc
Well-Known Member
Cool, thank you!
I actually changed the sediment, carbon, and DI filter the other day....added a booster pump also. Pumping at 98psi....i need to lower it a bit i think....and now getting 0 TDS out!!
I actually changed the sediment, carbon, and DI filter the other day....added a booster pump also. Pumping at 98psi....i need to lower it a bit i think....and now getting 0 TDS out!!
Opus
2500 Club Member
We still need to know your tap TDS and the TDS after the RO membrane. With new DI filter that will give you 0 TDS even if your RO membranes are shot. It just won't be 0 TDS for long. For example, lets say your RO membrane is working correctly and your TDS after the RO is 6. At 6 TDS your DI filter will produce around 740 gallons of 0 TDS water. Now if the RO membranes are shot lets say they are producing water with a TDS of 40. At 40 TDS your DI filter will produce around 110 gallons of 0 TDS water.
Cube reefer
Community Member
- Joined
- Dec 27, 2017
- Messages
- 26
- Reaction score
- 27
Hi, nob here, please explain what TDS is? I have had falling ph issues and now I wonder if my RO/DI is part of the problem. My water gets sent into a small holding tank and it pushes out the water from that. Should I run an air stone in the water a few days before adding to the tank?
redfishbluefish
Stay Positive, Stay Productive
Staff member
Super Moderator
Reef Squad
Partner Member 2024
Excellence Award
Article Contributor
NJRC Member
Hospitality Award
TDS is Total Dissolved Solids. It's an indication of the purity of the water.
If you have a holding tank, it sounds like you have RO only, and not DI. These water purifiers are made for purifying drinking water and typically attached to a sink with a special faucet to dispense that water. The issue with using the tank is that it has repeated start-ups, with it always needing to be filled. With each start-up, you get "break through" TDS, which means you have relatively high TDS when compared to TDS of a running RO system.
Your pH issue could be from carbon Dioxide being in the water. Are you on well water?
Randy Holmes-Farley
Reef Chemist
Staff member
Super Moderator
Excellence Award
Expert Contributor
Article Contributor
R2R Research
My Tank Thread
Assuming the water is reasonably pure, RO/DI is never a cause of low pH in the tank, no matter what you read it to be.
Reverse Osmosis/Deionization Systems to Purify Tap Water for Reef Aquaria by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2005-05/rhf/index.htm
Final Effluent pH
Aside from the issues discussed above concerning the effluent’s pH when the DI resin becomes depleted, the final pH coming out of an RO/DI system should not significantly concern reef aquarists. Many aquarists with low pH problems have asked, for example, if their aquarium’s low pH may be caused by their replacing evaporated water with RO/DI water that they measure to have a pH below 7. In short, the answer is no, this is not a cause of low pH nor is it something to be generally concerned about, for the following reasons:
1. The pH of totally pure water is around 7 (with the exact value depending on temperature). As carbon dioxide from the atmosphere enters the water, the pH drops into the 6’s and even into the 5’s, depending on the amount of CO2. At saturation with the level of CO2 in normal (outside) air, the pH would be about 5.66. Indoor air often has even more CO2, and the pH can drop a bit lower, into the 5’s. Consequently, the pH of highly purified water coming from an RO/DI unit is expected to be in the pH 5-7 range.
2. The pH of highly purified water is not accurately measured by test kits, or by pH meters. There are several different reasons for this, including the fact that highly purified water has very little buffering capacity, so its pH is easily changed. Even the acidity or basicity of a pH test kit’s indicator dye is enough to alter pure water’s measured pH. As for pH meters, the probes themselves do not function well in the very low ionic strength of pure freshwater, and trace impurities on them can swing the pH around quite a bit.
3. The pH of the combination of two solutions does not necessarily reflect the average (not even a weighted average) of their two pH values. The final pH of a mixture may actually not even be between the pH’s of the two solutions when combined. Consequently, adding pH 7 pure water to pH 8.2 seawater may not even result in a pH below 8.2, but rather might be higher than 8.2 (for complex reasons relating to the acidity of bicarbonate in seawater vs. freshwater).
cccharliecc
Well-Known Member
My tap water is around 120 TDS. I have not tested TDS ofter RO yet, I will try to do that today or tomorrow. I will have to juggle around my inline TDS meter to get those numbers.
