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JBL ProCristal UV-C 18W

by JBL
SKU J60367
Original price $370.00 - Original price $370.00
Original price
$370.00 - $370.00
Current price $370.00
  • Cristal-clear and healthy water: 18 W UV-C clarifier for the quick and efficient elimination of greenish and whitish cloudiness in freshwater and saltwater aquariums.
  • Space-saving assembly: connect to external filter. Inlet and outlet are positioned for practical use. With LED function indicator.
  • Germ-killing UVC radiation, reduces risk of infection, no change to the water values, no effect on cleansing bacteria in the filter.
  • TÜV tested, safety switch: automatically switches off the UV-C lamp when the device is opened. Sturdy, UV-resistant casing, 2- glass-cylinder design.
  • Package content: complete UV-C device, 5 m cable, UV-C bulb 18 W, socket: 2G11, wall mount, screws, nozzle hose connections for 16 - 32 mm hoses.
  • Guarantee: 2 years (+2 years upon registration of the product)


Crystal-clear and healthy water

  • Poor light conditions, over-fertilisation or even a surplus of nutrients can have negative effects on the aquarium water and may promote algae growth.
  • Floating algae lead to green, bacteria to white clouding.
  • The JBL water clarifier eliminates cloudiness caused by bacteria and floating algae.
  • The aquarium water passes through the sturdy UV-resistant casing of the clarifier.
  • The reflection of the UV radiation kills off bacteria, other germs and floating algae as the water passes through.
  • This can also help to eliminate persistent algae, such as thread algae, since their spores are also mostly killed off.

No harmful side effects

  • No change of the water values/no negative influence on the essential cleansing bacteria in the filter.

Easy to install

  • Connect the water clarifier to the external filter. Thanks to the 90° elbow included in the pack any installation position is possible.


  • The JBL UV-C Water Clarifier is TÜV tested and has a safety switch for an automatic switch off when the device is opened. The casing is UV-resistant and has sturdy walls.


Why is combatting cloudiness less effective than partial sterilisation?

> A partial sterilisation (against bacteria) is more effective than eliminating clouding caused by floating algae. Why? Because the cell structure of bacteria is quite simple. That’s why it is easier to destroy the cells of bacteria than those of algae.

JBL ProCristal UV-C: Can I store my water tests near the UV-C device?

>Storing water tests near a UV-C unit will not cause any problems.

JBL ProCristal UV-C: I had cyanobacteria in the aquarium and have removed them mechanically. There are probably still some freely floating around and I would like to know whether they can be killed off with UV-C.

> A UV-C lamp can also kill off cyanobacteria floating freely in the water.

JBL ProCristal UV-C: Can I run the UV-C water clarifier when using medications?

> When using medications you should definitely switch off the UV-C burner.

JBL ProCristal UV-C: How long does the device need to be in operation each day?

> From a distance we cannot assess how long your device needs to be in operation each day. For this we need to know the germ load and the regeneration of the germ density in the aquarium. However based on values of our own experience we would recommend running the device for an absolute minimum of 12 h a day. A continuous operation is, however, better for the durability of the burner.

JBL ProCristal UV-C: Does UV light destroy the active substances of my aquatic plant fertiliser?

> UV-C light degrades the chelators in the fertilisers which prevent the precipitation of trace elements, such as iron and some others. When using a UV-C clarifier we therefore recommend you switch to a daily dosing. At the beginning simply convert the standard dosage into a daily dose. It may be necessary later to increase the fertiliser dosage. Before each fertiliser application iron needs to be measurable at least in traces. Vitamins and other superior organic compounds also get degraded in the same way. Therefore a dosage of vitamins on the food is advised twice a week.

JBL ProCristal UV-C: What do you mean by flow rate and do I need to reduce the filter performance?

> By flow rate we mean the actual water flow through the UV-C water clarifier. If you connect the UV-C device behind the filter, all of the water which is run by the filter flows through the water clarifier, and the germ-inhibiting effect takes significantly longer (with regard to the total water amount of the aquarium). With powerful filters either the separate installation by means of a small circulation pump or the operation in bypass mode is recommended. This means running the water from the filter outlet to a y-piece (separation of the water), with the water clarifier installed in one of the water cycles, and then you can reconnect both hoses over a second y-piece, before the water flows back into the aquarium.

JBL ProCristal UV-C: When is the permanent use of the device recommended?

> When you have problems with bacterial infections on animals, the permanent use of the UV-C device is especially recommended. This is the only way to achieve an effective reduction of the germ load in the water. If no cases of illness are present, the operation can be limited to 12 h per day.

Enclosed with my ProCristal UV-C are several seals. Which should I use?

> For each connection fitting there is a seal in the carton and another fitting for the special elbow fitting. Thus for the 5 W and 11 W version 3 seals and for the 18 W and 36 W version five seals are enclosed. All the seals in the carton are the same size. Never use two on top of each other since this can lead to leakage. Please only use one seal for each connection.

How can I extend the performance of the JBL ProCristal UV-C devices?

> With the JBL QuickConnect you can join two ProCristal UV-C devices together. It doesn't matter whether they have the same performance.

Can a ProCristal UV-C 5W be equipped with an 18W bulb?

> No, unfortunately this is not possible. But you have the option to join a second ProCristal UV-C device to the 5W device with the help of the QuickConnect.

How much power does a JBL ProCristal UV-C 18 W water clarifier consume?

> A JBL ProCristal UV-C water clarifier consists of the UV-C burner and an electronic ballast. The ballast itself needs a low amount of electricity. The total output of the UV-C water clarifier is therefore slightly higher than the power, converted into UV-C light. Further information can be found on the type plate and the operating instructions.

How often does the glass cylinder need to be cleaned?

> Deposits (dirt, limescale etc.) inside the casing prevent the optimum efficacy of the UVC water clarifier. Therefore the inside of the appliance needs to be cleaned about twice a year, more frequently if the performance significantly deteriorates.

If I want to add JBL Denitrol to my aquarium, do I need to switch off the UV-C device?

> Yes, this would be useful. The bacteria need a little time to settle on the substrate. Until then they are floating freely in the water so that the UV-C radiation can kill them off. It is therefore recommendable to switch off the UV-C clarifier for a day.

In the instruction manual illustration for the JBL ProCristal UV-C the UV-C water clarifier is pictured connected behind the filter in an aquarium, yet it is pictured in front of the filter unit in the pond. What is the reason for that?

> A UVC water clarifier is generally connected at the outlet of the pump in order to ensure a proper flow.

In the majority of pond filters (with the exception of pressure filters), the filter holder is higher than the pond water level and the water flows out of the filter and down into the pond. The pond pump is in the pond. This is why the UVC water clarifier needs to be installed between the pump and the filter unit, to prevent the water from flowing back into it and blocking it.

I have green water in my aquarium, and even water changes and changing the filter media only helps for a short time.

Green water means floating algae, which grow when they have no competition from other plants and, even more, when the excrement of the fish creates excessive nutrient pollution in the water. The filter will not be able to do much about this. Ultimately, there are only two possibilities:

1. Carry out significantly more water changes in order to remove the nutrients caused by fish excrement.

2. A JBL AquaCristal UVC clarifier kills off the floating algae.

A temporary measure is to switch off the light for 2-3 days in order to stop photosynthesis in the algae.