Sizes: ½” x 4, 4 X 14, 14 x 40, 4 X
Surface Area: 24.9 square meters per
Weight: 55 pounds per cubic foot
CEC: Cation Exchange capacity 160 to
180 meq/100 grams
are a group of volcanic minerals that are hydrated
calcium potassium sodium aluminosilicates in which water
is held in channel ways by absorption. The lattices are
negatively charged, and they loosely hold positively
charged cations such as calcium, sodium, potassium, and
ammonium. Their ability to exchange one cation for
another is known as their “cation exchange capacity” or
CEC. Once the ammonium ion is in the lattice, it is not
water-soluble. They chemically filter out the ammonium.
zeolite is especially adapted as a direct replacement
for sand, sand and anthracite, and multi-media water
filtration media. It has a much finer nominal rating (3
to 5 microns) than sand (20 microns), and consequently
it filters out more fine particulates. See Usage
documents on water filtration.
INTRODUCTION TO AQUACULTURE
ammonia are the two most important parameters in
aquaculture. The oxygen is relatively easily controlled,
but the ammonia is much more difficult. Ammonia, the
un-ionized form of ammonia (ammonia gas) is produced
from the gills and urine from the fish as well as from
the bacterial decomposition of the unused food and fecal
material. Fish utilize the nitrogen component of
digested proteins, the amino group (NH2) to build new
proteins. However, when they utilize the proteins for
energy, they cannot metabolize the nitrogen, and the
amino group is split off as ammonia gas. Ammonia gas
solubilizes readily in water to form ammonium ion.
Ammonia is toxic, and it reduces the ability of the
hemoglobin in the blood to hold oxygen. Additionally,
ammonia damages the gill structure further impairing the
fish in getting oxygen.
three ways to reduce ammonia in the water. First would
include mechanical filtering of unused food and fecal
material. Although sand and charcoal have been used
extensively, zeolite is much more effective. It has a
nominal rating of 3 to 5 microns (sand is typically 20
microns), it loads 2 to 3 more times the particulate
load of sand, and it reduces the number of backwashes
(see usage document on water filtration). Second would
be the use of a biological filter in which bacteria
mineralize the organic nitrogen compounds. The process
can be aerobic or “nitrification,” or anaerobic or “denitrification.”
Nitrification is the most popular, and it involves the
oxidation of ammonia to nitrite and then to nitrates by
autotrophic bacteria (Nitrosomonas and Nitrobacter). The
huge surface area of BRZ™ makes it an excellent host for
bacteria. Third, the ammonia can be chemically filtered
by clinoptilolite. A zeolite filter system can be used
to mechanically remove food wastes and fecal material.
It also removes the ammonia and becomes a host for
aerobic bacteria that eat the ammonia. As such, it
becomes all three filter systems in one if properly
THE USE OF CLINOPTILOLITE IN AQUACULTURE
The ammonium promotes the growth of
algae in the pond or tank and the algae will grow on
the BRZ™ where they utilize some of the ammonium.
However, the algae on the BRZ™ will inhibit the
absorption of the ammonium into the BRZ™. The algae
must be washed off to accelerate the adsorption of
Excretion of ammonia by fish
increases with the activity of the fish, an increase
in the temperature, and an increase in the feed
ration. A rise of 13 degrees F can cause a 10-fold
increase in the rate of excretion.
The percentage of ammonia gas in
solution increases with an increase in temperature.
A reduction of dissolved oxygen (DO)
increases the acute and chronic toxicity of ammonia.
The toxicity of ammonia decreases
with an increase of salinity up to 30% sea water (9
Adsorption efficiency of BRZ™ is
unaffected by water temperature.
Adsorption efficiency of BRZ™
decreases in water of low pH.
Adsorption efficiency of BRZ™
decreases as water hardness increases. Other cations
such as Ca, Na, Mg, and K compete more effectively
than ammonium for the exchange position. Optimum
efficiency occurs when the hardness is less than 44
The effective depth of penetration
for ammonium into BRZ™ is about ½ inch. As a result,
smaller granules are more effective than larger
granules. Too many fines increase the turbidity,
BRZ™ will reduce ammonia in
proportion to the amount of BRZ™ used.
BRZ™ is typically not used in
seawater due to the high hardness and the amount of
sodium. In seawater, BRZ™ has approximately only 5%
of the capacity that it has in fresh water. Much
more massive amounts of BRZ™ must be used in
seawater that is typically not economic.
Ammonium loaded BRZ™ can be
regenerated by using a saline back wash solution
followed by a rinse cycle.
Alternatively, aerobic bacteria,
algae, or plants can be used to regenerate the BRZ™.
RECOMMENDED USES OF ZEOLITE FOR AQUACULTURE
-- Decorative rocks can be placed in ponds,
aquariums, streams, fountains, and other tanks.
Although these can be large in size, the effective
penetration is only about ½ an inch. Consequently,
BRZ™ larger than 1 inch diameter loses its
effectiveness as a chemical or chemical/biological
-- BRZ™ makes an excellent mechanical filter media
for unused food and fecal material or aquaculture
-- BRZ™ is an excellent chemical filter for
ammonium as well as for certain heavy metals by
virtue of its cation exchange capacity.
MEDIA FOR BIOLOGICAL FILTRATION.—the
tremendous surface area and irregular surface of
BRZ™ makes it a perfect media for biological
colonies of aerobic bacteria. In effect it becomes a
CONTROL OF AMMONIUM IN TROPICAL FISH BOWL - OCTOBER 2003
This test is designed to test the effectiveness of
ammonium reduction in a aquarium with one Betta fish
using two different zeolites: BRZ™ zeolite, and Brand X.
small fish bowls were prepared and filled with water
to study 3 groups of Betta fish.
was placed in each of four bowls designated the
“control group” with no zeolite.
was placed in each of four bowls containing a 0.3 oz
rock of zeolite screened at 1” x ¾” and designated
“Brand X” zeolite.
was placed in each of four bowls containing a 0.3
oz. rock of Bear River zeolite screened at 1” x ¾”
and designated “BRZ™.”
water was static. There were no pumps or aerators.
fish were fed two times per day 0.03 grams of food.
The results are in ppm ammonium.
Bowl Day 1 Day 2
Day 3 Day 4 Day