Changes from Blue to Amber when exhausted
Anion Single Bed Color Changing DI Resin is great for people
that want to be more efficient with their deionization resin
usage. Single bed resins do require the use of a cation and
anion resin followed by a mixed bed resin, but produce much
better results and are much more efficient!
Two Sizes Available:
1.4 lb Single Cartridge Refill
8.1 lb Bulk Package - up to 6 single cartridge refills
Deionization Resin
Reverse osmosis systems can remove up to 99% of contaminants
from your water, however, they can never remove 100% which is
the overall goal for reef tank water. That is where
deionization (DI) resin comes into play, by taking place as the
last "filter" of a RODI system after the membrane. DI resin is
ionically charged as either a cation (+) or anion (-) to
exchange hydrogen or hydroxide molecules for contaminants like
phosphate, silica, nitrate, sulfate, aluminum, iron, calcium,
etc allowing you to achieve 0 TDS water for your aquarium
and help eliminate any possible water quality issues. You may
or may not know that there are multiple types of DI resin
available from mixed bed to single bed resins that you can use
depending on what the specific goal is for your water and what
is in the water after the RO membrane.
Mixed or Single Bed
Single bed DI resins come in many different flavors, but at
heart only contain a single cation or anion that makes up the
entire media bed. Single bed resins are commonly used in
household water softeners and other applications that require
either the positive or negative ion to be removed and exchanged
for hydrogen or hydroxide ions. The concentration of a single
bed lets you focus on specific issues that you may have with
your water without wasting extra resin like a mixed bed resins.
Mixed bed resins contain both cations and anions in a single
bed of media that will remove both positively and negatively
charged ions from the water column. Mixed beds are very common
in residential RODI system that is used for reef tanks and
other types of aquariums since they are easy to use, but when
it comes to efficiency and cost savings, single bed systems are
the clear winners.
Cation or Anion
Cation = Positive Charge
Anion = Negative Charge
Choosing a single or mixed bed resin can be hard especially if
you do not know exactly what is in your water or how a RO
membrane will filter it. In most cases, you can use either the
cation or anion mixed bed resins but may notice that a TDS
meter is showing that the resin is exhausted before the color
has changed completely. That is more than likely due to an
excess of the opposite type of ion in your water when compared
to the color changing dye used in that resin. If this is
happening to you, changing to a resin with an opposite
indicating dye of your current will help with visual monitoring
as it becomes exhausted.
Mixed Bed Cation Resin (purple) -
Most commonly used after single bed resins to polish any
remaining contaminants. It contains both positive and
negatively charged ions and will change from purple to amber as
the cation resin is depleted. It is also perfect for single
canister DI systems that have an excess of positively charged
ions like calcium, magnesium, aluminum, ferrous and ferric
iron.
Mixed Bed Anion Resin (blue) - The
most commonly used resin in single or dual canister RODI
systems and contains both negative and positively charged. The
anion beads contain a blue color changing indicator that will
turn to an amber color when it is exhausted. This resin is
excellent for systems that have an excess of negatively charged
ions that are not removed by the membrane, like phosphates,
nitrates, sulfates, etc.
Single Bed Cation Resin (purple) -
Contains only cation beads that focus on removing positively
charged ions from the water that passes through it. As the
resin becomes depleted it will change from a purple to amber
letting you know at a glance when it is depleted. This is most
commonly used as the first stage in a single bed DI system.
Single Bed Anion Resin (blue) -
Anion resin focuses on removing negatively charged ions and has
a blue color changing dye that will change to amber as it
becomes depleted. Single bed anion resin is commonly used as
the second stage in a single bed DI system.
Color Changing
A majority of DI resin has a color changing indicator that will
change to a light amber color as the resin becomes exhausted.
The dye is simply a pH indicator that is stable at high or low
pH levels but will become translucent as the pH of the resin
becomes neutral and the resin becomes exhausted. With single
bed resins, there are some instances where your water may have
a high or low pH, and can cause the color indicating
dye to not become translucent, and that is why it is
imperative to use a TDS or conductivity meter to know
exactly when your resin is exhausted.
High pH water may interfere with the indicating dye contained
in anion (blue) single bed resin.
Low pH water may interfere with the indicating dye contained in
cation (purple) single bed resin.
Long Shelf Life
BulkReefSupply.com takes pride in the proper packing of our DI
Resin. DI resin begins depleting when exposed to air. To avoid
this, we package all of our DI resin in foil-lined 4mm Mylar
bags to prevent exposure to air that may deplete the resin
while it is waiting to be used. Our resin can remain packaged
this way for 2 years without losing its capacity. Our bulk DI
bags are perfect for reefers who process a lot of water or
otherwise go through resin quickly. Keep in mind once the seal
is opened the resin can start to deplete. Otherwise, purchase
the single refill packs for optimal freshness up to two years.
Specifications:
Polymer Structure: Styrene/DVB
Base Type: Strong
Polymer Type: Gel
Functional Group: Trimethylamine
Physical Form: Spherical Beads
Ionic Form (as shipped): Hydroxide
Total capacity: >1.0 meq/mL (OH Form)
Water Retention: 55 to 60 percent (OH Form)
Screen Size Distribution: 16 to 50 (U.S. Mesh)
Maximum Fines Content: 1 percent (less than 50 Mesh)
Minimum Sphericity: 93 percent
Uniformity Coefficient: 1.6 (Approximate)
Resin Color: Blue
To get maximum life from your DI resin please takes the
following steps
- Ensure optimal operation of your RO membrane. The higher
your membranes rejection rate the fewer TDS your product water
will contain resulting in longer lasting resin. The best way to
keep the membrane rejection rate up is to monitor and change
your prefilters appropriately as well as maintain at least
50psi going into the membrane.
- Ensure the resin is packed in the cartridge securely. The
resin should be packed very tightly. When squeezed, there
should be almost no flex to the cartridge.
- The initial couple minutes of water from your RO membrane
will always be high, this is commonly referred to as TDS creep.
Diverting the first few minutes of water down the drain can
often greatly reduce DI resin consumption.
- Maintain low levels of carbon dioxide in your water supply.
Excess carbon dioxide will deplete DI resin quickly. If you are
depleting resin quickly and have already: addressed the two
options above, excess carbon dioxide is the likely culprit. You
have two choices:
- Collect the water coming from your RO system in a large
container, add a powerhead or airstone and allow the CO2 to
gas off. Then pump the water through your DI resin.
- Skip all that mess and just buy resin in bulk.
Common Contaminants:
Molecule Name
|
Ionic Charge
|
Removed By
|
Sodium
|
+1
|
Cation Resin
|
Calcium
|
+2
|
Cation Resin
|
Magnesium
|
+2
|
Cation Resin
|
Aluminum
|
+3
|
Cation Resin
|
Ferric Iron
|
+2
|
Cation Resin
|
Ferrous Iron
|
+3
|
Cation Resin
|
Chloride
|
-1
|
Anion Resin
|
Bicarbonate
|
-1
|
Anion Resin
|
Carbonate
|
-2
|
Anion Resin
|
Sulfate
|
-2
|
Anion Resin
|
Nitrate
|
-1
|
Anion Resin
|
Phosphate
|
-3
|
Anion Resin
|
Silcate
|
-4
|
Anion Resin
|