this helps against green water, need to get the right power for the right capacity of water tank.
UV Sterilizers: Which one is right for you?
Drs. Foster & Smith Educational Staff
Microscopic organisms can be one of your aquarium's worst enemies. A UV sterilizer is a great way to help protect both current aquarium inhabitants and new additions from the health risks presented by bacteria and parasites. UV sterilizers use a special fluorescent UV lamp that produces light at a wavelength of 253.7 nanometers. Aquarium water is pumped past the lamp at a low flow rate and is essentially "irradiated," controlling free-floating bacteria, algae and parasites.
When choosing a UV sterilizer, ask yourself the following questions:
What kind of organisms do I wish to control? Bacteria, parasites, or both?
What is the proper flow rate required to accomplish my goals?
Do I want an in-line or hang-on unit?
Differences in UV Sterilizers
UV sterilizers differ in a number of ways. The first is their position in the water flow- either in-line or hang-on. In-line models are plumbed into the system after the mechanical filtration unit, as the last filter in line before water returns to the aquarium. You may need to use a ball valve or a "T" connector in your return line to slow down the flow rate going to the UV sterilizer.
Tips from our Techs
Always locate UV filters after mechanical filtration to help slow buildup on the quartz sleeve, thus requiring less maintenance in the long run.
Hang-on models are mounted on the back of the aquarium and are usually fed by a submerged power head or a return line from a canister filter. These models are easier to install and somewhat easier to maintain.
Another difference is the use of quartz glass sleeves. Some models feature a quartz sleeve, which increases the brightness and effectiveness of the unit. Some models claim that their designs results in a longer "dwell time," which may enhance effectiveness as well.
Choosing the Right Size Unit
For proper use, the UV sterilizer must be matched to the proper flow rate to ensure an efficient "kill dose" for the organisms you wish to eliminate. A slower flow rate is required for controlling parasites, as they are more resistant to irradiation than are bacteria.
UV Bulb
(Watts) To Control
Bacteria and Algae
(gph) To Control
Parasites
(gph)
4 60 N/A
8 120 N/A
15 230 75
18 300 100
25 475 150
30 525 175
40 940 300
65 1700 570
80 1885 625
120 3200 900
130 3400 1140
The chart provides guidelines for determining the bulb size and flow rate you require for UV sterilization. To use this chart, identify the maximum GPH rating in either column that most closely matches the number of gallons in your aquarium. The maximum flow rate should be greater than the number of gallons in the system (tank & sump).
For example, if you have a 100 gallon tank and want to control parasites, you would need a minimum 18 W UV with a maximum flow rate of 100 GPH. A 25 W UV at a flow rate of 150 GPH would be preferable. With UV sterilizers, bigger is better.
Operating Guidelines
While UV sterilizers usually do no harm, do not use one when you first cycle your aquarium, as it may kill beneficial bacteria before they attach to the bio-media or gravel. Also, many medications can be "denatured" by the UV light, so the sterilizer should be turned off when using medications, especially chelated copper treatments. The UV light will "break" the bond of the chelating agent, and the aquarium will have a sudden, lethal concentration of ionic copper.
Once you introduce a UV Sterilizer into your system, carefully monitor your aquarium's temperature. Depending on your aquarium size and flow rate, a UV Sterilizer may add heat to your aquarium water. If this occurs, you may wish to consider installing a chiller.
Maintenance Requirements
As with all sophisticated pieces of equipment, your UV Sterilizer needs to be properly maintained to remain effective. Quartz sleeves should be cleaned at least every six months. UV bulbs will need to be replaced after 9 to 12 months of continuous use.
UV sterilizers have many advantages and very few drawbacks. In addition to being easy to install, requiring low maintenance, and being affordable, they can provide huge health benefits for your fish. Make sure you get one that is the correct size, operate it under the appropriate conditions, and follow the manufacturer's maintenance guidelines to ensure that your UV sterilizer can do the job it was designed for.
Plumbing Your UV Sterilizer
Drs. Foster & Smith Educational Staff
Time spent up front getting acquainted with the plumbing needs of UV sterilizers streamlines installation and maintenance.
Stable water parameters, proper diet, and regular water changes are the keys for disease prevention and a healthy, successful aquarium. However, the addition of sophisticated equipment such as an ultraviolet sterilizer to a quarantine tank can further minimize the spread of free-floating bacteria and parasites. Ease of installation or plumbing can play a large role in selecting an appropriate UV sterilizer.
UV sterilizers can be plumbed in two ways, either "hard plumbed" or "soft plumbed." Hard plumbing is a permanent installation involving adhesives and PVC piping, while soft plumbing is semi-permanent involving flexible tubing and clamps. Knowing the plumbing style of the fittings on a UV sterilizer helps you select a compatible pump, as well as other plumbing supplies. Fittings for UV sterilizers come in three styles:
Barbed/Insert fittings - Commonly soft plumbed and the easiest to plumb since the appropriate-sized flexible vinyl tubing is simply fitted onto it and secured with clamps. Most hang-on sterilizers will have barbed fittings.
NPT (National Pipe Threading) fittings - Sterilizers that incorporate NPT fittings are either MPT (male pipe thread) or FPT (female pipe thread). Depending on your current system, NPT fittings can be hard or soft plumbed. However, the use of "NPT x Insert Adapters" can make plumbing easier since they convert NPT fittings to barbed or insert fittings.
Slip fittings - Usually hard plumbed but a combination of both plumbing methods can be applied using reducing bushings. A "Slip x FPT Reducing Bushing" converts a slip fitting to a NPT fitting which is then converted to a barbed or insert fitting for easy installation.
Spending some time up front getting acquainted with the plumbing needs of UV sterilizers can streamline installation and maintenance. Because UV bulbs need to be replaced at least once a year, a properly plumbed system will mean easier maintenance. By having all the necessary plumbing supplies on hand, installation will be quick, so you can start to see the benefits of your UV sterilizer sooner.
UV Sterilizer Selection Guide
Drs. Foster & Smith Educational Staff
Use the following chart to help you choose the best UV sterilizer for your application:
UV Sterilizer Comparison Chart
Model Watts In-line or Hang-on Quartz Sleeve Special Features
Aqua UV Sterilizers 8-120 Watts In-line Yes Optional wiper/bulb cleaning system;
14-month lamp;
EPA registered
Lifegard UV Sterilizer Modules 8-120 Watts In-line Yes Includes all-quartz bulb;
Optional horizontal mounting kit;
EPA Registered
Ocean Clear Multi-Function UV Sterilizers 18 Watts In-line Yes Includes additional mechanical filtration; optional biological filtration for finely polishing water
Angstrom 2537 Sterilizers 4-15 Watts 4, 8 W- Hang-on
15W- In-line Yes Compact, easy to install and maintain
TurboTwist 3X UV Sterilizer 9 Watts Hang-on and In-line Yes Quartz sleeve and twist design provide 3 times more UV exposure;
Hang-on tank bracket included
Tetratec UV5 Clarifier 5 Watts In-line Yes Built-in Starter; durable; easy installation
Gamma UV Sterilizer 8- 40 Watts In-line, Hang-on, & Wall-mount Yes You choose the mounting; water passes through housing in a spiral, providing longer contact time
Choosing the Right Size Unit
The chart below provides guidelines for determining the bulb size and flow rate you require for UV sterilization. To use this chart, identify the maximum gph rating in either column that most closely matches the number of gallons in your aquarium. The maximum flow rate should be greater than the number of gallons in the system (tank & sump).
For example, if you have a 100 gallon tank and want to control parasites, you would need a minimum 18 W UV with a maximum flow rate of 100 gph. A 25 W UV at a flow rate of 150 gph would be preferable. With UV sterilizers, bigger is better.
UV Bulb
(Watts) Maximum Flow Rate for
Controlling Bacteria and Algae Maximum Flow Rate for
Controlling Parasites Aquarium Size
8 120 gph N/A under 75 gallons
15 230 gph 75 gph 75 gallons
18 300 gph 100 gph 100 gallons
25 475 gph 150 gph 150 gallons
30 525 gph 175 gph 175 gallons
40 940 gph 300 gph 300 gallons
65 1700 gph 570 gph 570 gallons
80 1885 gph 625 gph 625 gallons
120 3200 gph 900 gph 900 gallons
130 3400 gph 1140 gph 1140 gallons
Operating Guidelines
While UV sterilizers usually do no harm, do not use one when you first cycle your aquarium, as it may kill beneficial bacteria before they attach to the bio-media or gravel. Also, many medications can be "denatured" by the UV light, so the sterilizer should be turned off when using medications, especially chelated copper treatments. The UV light will "break" the bond of the chelating agent, and the aquarium will have a sudden, lethal concentration of ionic copper.
Once you introduce a UV Sterilizer into your system, carefully monitor your aquarium's temperature. Depending on your aquarium size and flow rate, a UV Sterilizer may add heat to your aquarium water. If this occurs, you may wish to consider installing a chiller.
Maintenance Requirements
As with all sophisticated pieces of equipment, your UV Sterilizer needs to be properly maintained to remain effective. Quartz sleeves should be cleaned at least every six months. UV bulbs will need to be replaced after 9 to 12 months of continuous use.
UV sterilizers have many advantages and very few drawbacks. In addition to being easy to install, requiring low maintenance, and being affordable, they can provide huge health benefits for your fish. Make sure you get one that is the correct size, operate it under the appropriate conditions, and follow the manufacturer's maintenance guidelines to ensure that your UV sterilizer can do the job it was designed for.
