Changes from Purple to Amber when exhausted
Cation 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 resins followed by a mixed bed resin, but produce much
better results, and are much more efficient!
Two Sizes Available:
1.25 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.
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.
