How long does a UV-C device need to be in operation each day?
Without an onsite assessment we are unable to recommend how long your UV-C device needs to be in operation each day. For this we need to know the germ load and the regeneration level 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 bulb.
Does a UV-C device kill free floating cyanobacteria in the aquarium?
I have mechanically removed cyanobacteria in the aquarium. Some of them must be floating around freely now.
The JBL PROCRISTAL UV-C Compact plus can also kill off cyanobacteria floating freely in the water.
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.
Can I store my water tests near a UV-C device?
Storing water tests near a UV-C unit will not cause any problems.
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.
Does UV-C 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 dosage. At the beginning simply convert the standard dosage (of e.g. JBL PROFLORA Ferropol 24) into a daily dose. It may be necessary to increase the fertiliser dosage. Before each fertiliser application iron needs to be measurable at least in traces. Vitamins and other superior organic compounds are also degraded in this process.Therefore we advise you add a dose of vitamins to the food (e.g. with JBL Atvitol) twice a week.
How much electricity does a JBL ProCristal UV-C 5 W - 36 W 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.
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.
If I want to add live bacteria to my aquarium, do I need to switch off the UV-C device?
Yes, this would be useful. The bacteria, as for example in JBL Denitrol or JBL PROCLEAN BAC, 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 device for a day.
In the instruction manual illustration for the JBL PROCRISTAL UV-C, the UV-C device is pictured connected behind the filter in an aquarium, yet it is pictured in front of the filter unit in the pond. Why is that?
A UV-C device 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 canister is higher than the pond water level and the water flows out of the filter then flows freely downwards back 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 keep backwater out of the UV-C device.
What helps with green water in the aquarium?
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 options:
1. Carry out significantly more water changes in order to remove the nutrients caused by fish excrement.
2. A JBL PROCRISTAL UV-C Compact plus 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.