Proprietary media engineered to remove fine sediment, nutrients, petroleum hydrocarbons as well as dissolved metals. Can contribute towards earning LEED points for your project. Product Availability. Add to Quote Generator. Quote Generator Looking for a quote for your project? System water should be free of residual chlorine that may have been used for disinfection or pathogen control. System water should be warmed or cooled to near the temperature at which the system will be operated when stocked; pH, salinity, alkalinity and hardness should match the requirements of the incoming stock.
Provide alkalinity, a carbon source Carbon dioxide dissolved in the system water is a source of carbon for the developing bacteria cells, but carbonate CO3 -2 and bicarbonate HCO 3 - ions are also carbon sources and are more easily added and controlled. Add sodium bicarbonate NaHCO3 , or common baking soda, to increase alkalinity.
Baking soda is inexpensive and safe to use. When Nitrobacter does become established, alkalinity can be allowed to decline to operational levels. The alkalinity of your water source will affect the quantity of sodium bicarbonate needed to raise the system alkalinity to suitable levels. Sponsor message. Aquaculture is an increasingly important source of safe, nutritious, and sustainable seafood for people worldwide.
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During the start-up of a new system, this is unlikely unless the source water is high in carbon dioxide. Circulation and aeration or degassing of the water in the system will reduce CO 2 concentration. Provide ammonia and nitrite Add ammonium hydroxide, or unscented household ammonia used for cleaning, which is an aqueous solution of ammonia. Ammonium chloride and ammonium nitrite also are commonly used. This should allow for good detection by most testing methods.
Adjustments will be necessary if you are using a different concentration of aqueous ammonia. Start with a minimum amount, allow enough time for thorough mixing through the system, and then test for the ammonia concentration. Introducing bacteria may accelerate the acclimation process. Apply the suggested nutrients at the rates and schedules directed by the manufacturer. Directions may suggest that bacteria be added in several portions. The most effective way to introduce bacteria is to move biomedia elements from an acclimated system operating under similar culture conditions.
If introducing already colonised biomedia elements or other forms of bacteria, add them at this time. Water quality parameters should be monitored regularly during the start-up of a biofilter. Ammonia, nitrite, pH, temperature and alkalinity are the primary water quality parameters to test. Reliable, accurate and repeatable methods for measuring ammonia and nitrite concentrations in the system should be established.
Testing can be done with test kits and colour comparators, colorimeters, or spectrophotometers. Operators should be able to compare changes in water quality from one day to the next with confidence that the test results are representative of changing water quality conditions that the biofilter is causing.
Water samples should be collected from the culture tank, since that is where the animals will be. Samples should be collected from the same place in the tank and analysed promptly. They should be taken at the same time each day, and persons conducting tests should follow the same procedures, using the same accurate measuring equipment. Standardisation, routine, and attention to detail ensure that you will have accurate information for making operational decisions. This gives you a visual concept of biofilter development.
Figure 1 shows the characteristic curves associated with biofilter start-up. While the numbers may vary among different cycles, systems and biofilters, the shape and relationship of the curves should be about the same. Initially, ammonia concentration increases to a high point and then declines. After a lag period, nitrite concentration begins to increase to a point and then declines. All water should come in contact with this mesh part of the filter before it reaches any biological or chemical filter media.
Mechanical media is intended to remove larger particles from the water, thus eliminating clogging in other areas of the filter. Placing it first in line allows much of the debris to be captured before the water continues on to the other filter media. Types of mechanical filtration media include filter wool or floss, bonded pads, or sponges.
While some of these can also serve a dual purpose as biological media, it is important to remember that any mechanical filter media must be removed and replaced frequently, so some bacterial colonies will be lost. Some owners prefer to use sponges and pads material as both mechanical and biological media. When dual-purpose media is used, you need several layers, preferably of differing degrees of coarseness.
The coarsest material is placed in first. Because the sponges are serving as both mechanical and biological media, each layer should be cleaned at different times. By staggering the cleaning schedule, they will have time to repopulate the cleaned zones. This way, there is less overall disruption to the bacterial colonies. Biological media bio-media is usually placed after the mechanical media but before any chemical media.
The biological media must not become clogged, as it serves as the right substrate for colonies of beneficial bacteria. If clogged, the oxygen flow will be impeded, putting the bacterial colonies at risk of die-off.
Biological filtration media are like condominiums for bacteria. Types include ceramic rings, sponges, pads, bio balls and bio stars, sand, and gravel. Keep in mind that some of these materials can also be used as mechanical media. These porous objects have high surface areas while still allowing the passage of water and light to flow through them; they make excellent homes for bacteria.
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