Important facts about carbon dioxide in natural waters
Tropical waters, especially flowing waters, exhibit a surprising degree of stability, independent of the season, water level and light conditions. Factors such as pH value, CO2 content, degree of hardness etc. show only a slight fluctuation in range. Therefore, stability of all parameters is of great importance for the aquarium as well. The Dupla CO2 system ensures stability in the aquarium:
1. Constant pH value.
In the optimum community aquarium where tropical fish from geographically and chemically differing waters can be cared for, a neutral pH value is recommended.
The CO2 system also offers great advantages for the specialised aquarium in which special fish species, such as discus fish, can be cared for or bred. Due to the precisely controlled CO2 dosage, both acid and alkaline pH ranges are able to be programmed and set so as to be stable.
2. Stable carbonate hardness.
If an aquarium suffers from CO2 deficiency, the following will occur: Carbon is chemically bound in carbonates. Without sufficient 2 the plants need this bound carbon. Through the process of biogenic decalcification, the carbonates are broken down, the carbonate hardness drops to dangerously low values, and the pH value becomes extremely unstable. With sufficient CO2 supply however, the plants utilise the carbon contained in the carbon dioxide. Biogenic decalcification no longer occurs and water stability is assured.
3. Optimum carbon supply for plants.
Submerged water plants obtain their carbon requirements preferably from dissolved gaseous carbon dioxide in the water. With the Dupla CO2 system, optimum carbon supply is provided.
Dupla, the pioneer of CO2 fertilisation, offers a wide range of products for both small and large aquariums. Currently, there are three main CO2 sets for aquariums up to 150L, 200L & 400L respectively. These may be combined with accessory products to provide semi-automatic, and fully automatic CO2 systems. A CO2 system may also be assembled from components to provide a premium system cable of supplying the CO2 needs of aquariums up to many thousands of litres capacity.
The CO2 Set Delta 400 is recommended for aquaria up to approximately 400 litres. The set is based around the Dupla CO2 Reactor 400, a unique and sophisticated device for optimum CO2 infusion. In the Reactor 400, water from the filter pump's by-pass, trickles over the internal cascade, mixing with inflowing CO2 gas, thereby creating a large increase in CO2 diffusion capacity.
This set provides everything the aquarist needs for a good and quick start with CO2 fertilisation in his aquarium up to 200 litres capacity. The Dupla CO2 Set 200 includes a Dupla CO2 Depot of aluminium, with a capacity of 750g CO2 gas, with safety cage and the pressure reducer fitting Delta. The CO2 Set Delta 200 also includes a CO2 atomiser (with integrated Duplasafe non-return valve) which evenly distributes the CO2 gas within the water, the CO2 visual test, and all necessary tubing etc are also included.
The CO2 Permanent Test is a cleverly constructed monitoring device, by which, the correct carbon supply for aquarium plants can be adjusted. The bell's inner part is linked to the aquarium water by an air duct, enabling the indicator to react to the level of carbon dioxide in the water: green = optimum level, yellow = too much, blue = insufficient CO2. The supply of CO2 must be adjusted so as to keep the indicator liquid constantly green. The specifically intelligent feature of this small device however, is the fact that only changes in acid levels caused by carbon dioxide are displayed, and not changes caused by mineral or organic acids.
CO2 pressure gas cylinders of aluminium. Currently available in the sizes 750g and 1500g.
The Dupla CO2 Armatur (or Fitting) Delta uses a piston type regulator, that is factory pre-set to 1 bar output pressure. It is supplied with an easy to handle knurled nut for cylinder connection, and a precise and easily adjustable flow control needle valve. The body is machined from solid brass, and is supplied with a high pressure gauge to indicate cylinder contents.
The new Dupla CO2 Fitting Alpha Mk II is the natural successor for the original Fitting Alpha. This new model is CNC milled from solid aviation grade alloy - another industry first for Dupla. As with all Dupla CO2 equipment, the Fitting Alpha Mk II has a standard cylinder coupling to mate with the Dupla 750g or 1500g aluminium cylinders, as well as larger commercial rental cylinders. Using a robust piston style pressure regulation, with the time proven Dupla precision needle flow-control valve, plus both cylinder content and line pressure gauges, the Dupla CO2 Fitting Alpha Mk II has already earned it's place at the top of the extensive Dupla CO2 system line-up.
The Dupla CO2 Atomizer is a small CO2 'reactor' for CO2 fertilisation in small aquaria. The CO2 gas is passed through a fine sintered glass diaphragm and released into the water as a cloud of tiny gas bubbles. The clever physical trick with the atomizer: the gas bubbles are met by surrounding water movement as they rise, thereby releasing CO2 into the water. CO2 is now available to the plants.
This device is recommended for aquaria up to a volume of 400 litres. In the Reactor 400, a bypass of water from the filter pump, trickles over the internal cascade, mixing with inflowing CO2 gas. This enables a large diffusion capacity.
The CO2 Reactor S is perfectly suited for the optimum and almost maintenance-free CO2 fertilisation in large aquaria. In conjunction with the Dupla CO2 magnetic valve and the control devices Dupla pH-Control Delta or pH-Control Alpha, it forms a fully automatic, intelligent CO2 fertilisation system for aquaria.
The Dupla CO2-Magnetic Valve enables semi or fully automatic CO2 control. It has a high quality brass valve body and provides reliable functioning at all times. For semi-automatic operation, it is connected to the lighting timer so that CO2supply is switched off with the lights. For fully automatic operation, it is used with a pH Control Delta or Alpha.
This non-return valve is used to prevent water from flowing back along the CO2 line, and causing damage to the Magnetic Valve or Pressure Reducer. It should be installed between the Magnetic Valve and the Reactor.
A practical pH control device utilising analogue technology, with 3 digit, green LED display. The adjustment of the set value and calibration, are effected by means of potentiometers.
The Dupla pH-Control Alpha is a RISC microprocessor based pH control device with a three segment LED display. The set value and alarm limits are entered by means of membrane keys. The state of the switching unit is indicated by the green LED in the display of the control panel.
The Dupla Multi Control Aquarium computer with six-way socket for control of all key parameters in freshwater and seawater aquariums using a single device. Enables pH-controlled CO2 fertilisation, while the the water temperature is regulated by a fitted temperature sensor. The socket for ground temperature management is controlled by way of the variable hysteresis to the water temperature and, due to an inverting function, allows a cooling device to be connected instead of the ground heating. Fitted with three time-controlled sockets for devices such as day/night lights, air and hydraulic pumps, or filters, which can be switched on and off up to 8 times per day.
A laboratory grade, electrode for premium results and long-life. Constructed from glass, this pH electrode may be refilled to extend its useful service life. It has a wide measurement range of pH 0 to 13,5 and a temperature range of -5°C to +80°C.