JBL AquaCristal UV-C: How long should the burner be on every day ?
It's not possible to make a general statement as to how long the burner should be on every day without seeing the aquarium, as information such as the germ load and the germ growth rate of the aquarium is required. However, in my experience, I would not keep the 36 W burner on for less than 12 h daily. In terms of the service life of the burner, non-stop operation would be preferable.
JBL AquaCristal UV-C: When is non-stop operation of the burner advisable?
Particularly if you are experiencing trouble with bacterial infections of the animals, non-stop operation of the UV-C water clarifier is advisable. This is the only way to achieve effective reduction of the density of microbes in the water. If no diseases are present, operation can be limited to 12 h per day.
JBL AquaCristal UV-C: Does a UV-C water clarifier heat up my tank water?
It is relatively unlikely that a UVC water clarifier will heat up tank water, at least to the extent you have indicated. The so-called delta temperature, that is the difference in temperature between the temperature setting and the temperature actually reached, as well as the room temperature, would be important for an assessment.
JBL AquaCristal UV-C: Does the ultraviolet light destroy active ingredients of my aquatic plant fertiliser?
UVC light degrades the chelators in the fertilizers, which prevent the precipitation of trace elements such as iron, among others. Therefore, when using a UVC water clarifier, it is advisable to change over to daily fertilisation. The standard dose needs to be converted into a daily dose at the beginning. It may also be necessary to increase the fertiliser dose slightly. Iron should be detectable in traces at least prior to each subsequent application of fertiliser. Vitamins and other higher grade organic compounds may likewise be broken down. Therefore, when using vitamins, it is advisable to add the fertilizer with the food twice a week.
JBL AquaCristal UV-C: What do you mean by flow rate, and should I reduce the filter output?
Flow rate refers to the actual rate of flow through the UV-C water clarifier. If the UV-C water clarifier is connected behind the filter, all of the water cleaned by the filter flows through the clarifier and the sterilising effect lasts much longer (relative to the total amount of water in the tank). When using a filter with a high output, we recommended you either use separate installation by means of a small circulation pump or operation in a bypass, i.e. from the filter outlet into a Y piece (separation of the water), next, to install the clarifier in one of the circuits and then to connect the two hoses again by using a second Y piece, and then to lead them back into the tank.
JBL AquaCristal UV-C: Can I store my water tests near the UV-C appliance?
Water tests can be stored near a UV-C water clarifier with no trouble, as the bluish light that "shines out of" the hose connector is harmless. Besides this, the liquid reagents are contained in dark plastic bottles.
After two weeks, there is still slight whitish cloudiness in the tank. Therefore, I would like to purchase a UV-C clarifier.
What output do I need to get ?
Please check the table in the instructions for use which can be downloaded at https://www.jbl.de/?lang=en&mod=products&func=detail&id=7404.
JBL AquaCristal UV-C: There are sure to be some of them floating around now, and I would like to know whether they will be killed by a UV-C water clarifier.
A UV-C lamp kills all of the organisms floating around in the water, to the effect that the cyanobacteria will be killed as well.
What sterilisation rate in % does the JBL AquaCristal UV-C 36 W clarifier achieve with a power input of 36 W and a flow rate of approx. 1000 l/hour?
The 36 W UVC water clarifier is designed for partial sterilisation with a flow rate of 200 - 400 l/h. It can achieve up to 90 % reduction of microbes in the water flowing out. The higher the flow rate, the more the sterilisation rate decreases.
One must bear in mind that the organisms' sensitivity to UVC radiation differs significantly. Pathogenic germs and yeasts are more sensitive to UVC radiation than some mould spores, which, accordingly, require a higher UV dose.
The following equation is decisive: UV dose (mWs/cm²) = Intensity (mW/cm²) x Time (s)
The total reduction of microbes in an aquarium must be determined methodically for each individual case, which is very difficult, as the growth of microbes within the aquarium system must be taken into account in addition to the actual killing of microbes. This growth, in turn, is subject to enormous fluctuations and varies from one aquarium to the other.
However, you are on the safe side with a 36 W water clarifier for a 720 l tank. Ultimately, it is recommended to use a lower flow rate up to max. 400 l/h.
How much electric power (Watts) does my AquaCristal UV-C water clarifier need for a partial sterilization?
In the instruction booklet for the JBL AquaCristal we recommend the 18 W UV-C water clarifier for a partial sterilization of aquariums of up to 400 l max. and with a flow rate of up to 200 l/h. For a more extensive germ elimination the use of the bigger 36 W clarifier is advisable. Here the recommended flow rate of about up to 400 l/h needs to be taken into account. This makes a bypass connection advisable for most of the usual external filters in such aquariums.
Size of JBL AquaCristal UV-C 36 W ?
The data refer to the installed appliance without control gear:
Length incl. of cable gland: 53.5 cm
Housing diameter: 8.5 cm
Diameter without hose tails and incl. back nuts: 10.5 cm
Diameter without hose tails and incl. back nuts and mount: 13 cm
Diameter with the hose tails (maximum) and incl. back nuts and mount: 19 cm
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.
Do I have to turn off the UV clarifier when I add JBL Denitrol to my aquarium?
Yes, this is necessary. 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 48 hours.
In the graphic depiction in the instructions for use for JBL AquaCristal UV-C, the UV-C water clarifier is connected behind the filter in an aquarium, whereas it is connected before the filter unit in a pond. Why is that so?
A UVC water clarifier is generally always connected behind 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.