Puritech RO unit maybe faulty?

Discussion in 'Test Kits, Controllers, Reactors and Dosers' started by Mac75, 13 Sep 2012.

  1. Mac75

    Mac75

    Joined:
    9 Jul 2011
    Posts:
    446
    Likes Received:
    10
    Location:
    19209km from Hawaii
    Hi guys pls advise:

    Bought a puritech unit earlier this week from a sponsor. Its a 4 stage unit. On first install i let it run for about an hour and after that let it produce about 75L of RO water. The RO water has a ph of 6 and ammonia reading between 0 and 0.5mg. Is this ok or is the unit faulty? Thanks.
     
  2. Guest




  3. Quintin

    Quintin

    Joined:
    30 Aug 2010
    Posts:
    1,607
    Likes Received:
    38
    Location:
    Ruimsig
    Ammonia and PH is not filtered or changed by your R/O unit.
    It only removes Total Dissolved Solids in the water (TDS)

    "Ammonia will pass fairly readily through an RO membrane (discussed later in this article), but if there is a DI system, it should effectively remove ammonia."

    You need to add a DI resin filter to the unit to remove this.

    "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."


    Here is an article for you on the subject.
    http://reefkeeping.com/issues/2005-05/rhf/index.php
     
    Last edited: 13 Sep 2012
  4. OP
    Mac75

    Mac75

    Joined:
    9 Jul 2011
    Posts:
    446
    Likes Received:
    10
    Location:
    19209km from Hawaii
    Thanks Quintin. It looks like the fourth stage is a resin filter, goldish brown crystals?
     
  5. dallasg

    dallasg Moderator

    Joined:
    14 Dec 2008
    Posts:
    16,802
    Likes Received:
    591
    Location:
    Sandton
    you can go directly to puritech and get the DI addon from them
     
  6. Quintin

    Quintin

    Joined:
    30 Aug 2010
    Posts:
    1,607
    Likes Received:
    38
    Location:
    Ruimsig
    Yip, that should be your DI resin.
     
  7. OP
    Mac75

    Mac75

    Joined:
    9 Jul 2011
    Posts:
    446
    Likes Received:
    10
    Location:
    19209km from Hawaii
    Does this mean the DI resin is not working properly?
     
  8. Quintin

    Quintin

    Joined:
    30 Aug 2010
    Posts:
    1,607
    Likes Received:
    38
    Location:
    Ruimsig
    No idea man.
    To be honest I have never tested Ammonia of PH from the R/O unit.
    Only check for TDS.

    Best guy to ask would the http://www.thewaterboy.co.za
    Believe he is also a sponsor and may be able to point you in the right direction.
     
  9. OP
    Mac75

    Mac75

    Joined:
    9 Jul 2011
    Posts:
    446
    Likes Received:
    10
    Location:
    19209km from Hawaii
    Cool. Thanks.
     
  10. butcherman

    butcherman Moderator

    Joined:
    7 Sep 2009
    Posts:
    11,685
    Likes Received:
    290
    Location:
    Kempton Park
    perhaps the DI resin is exhasted?
     
  11. mornewil

    mornewil Morne

    Joined:
    23 Jun 2011
    Posts:
    1,846
    Likes Received:
    156
    Location:
    Retreat, Cape Town
    This is why i add some aquavitro alpha into my water before i use it.
    There was a thread some time ago about this.
     

Recent Posts

Loading...
Similar Threads - Puritech unit maybe Forum Date
[wtd] Dual 24w T5 Unit Wanted 22 Jun 2017
Oddysea 150 cm 80w Light Unit Double Dorry Pets 21 Jun 2017
[wtd] 54w t5 light unit Wanted 29 May 2017
RO unit General Discussions and Advice 29 May 2017
[wtd] Zetlight Lancia Zp4000 Control Unit and Remote Wanted 21 May 2017
[wtd] Pacific Sun Unit or Radion Wanted 14 May 2017
[wtd] Reef aquatics led unit 120cm or 90cm Wanted 13 May 2017