Water cloudiness

Here’s how to make your cloudy aquarium water crystal-clear again

Two kinds of cloudiness mostly occur: greenish and whitish water cloudiness. In addition there are colour casts which make the water look brownish or yellowish.

We have the following tips for you here:

Whitish water cloudiness

In most cases this is caused by bacteria/microorganisms and it disappears on its own after 1 – 2 days. If not, the application of a PROCRISTAL water clarifier can help. The power (wattage) of the UV-C water clarifier depends on the water volume of the aquarium.

Operating principle: The water inside the UVC water clarifier flows relatively slowly along the germ-killing UV-C radiation. These kill off the germs and bacteria, as well as the floating algae. Their whitish cloudiness will completely disappear within 1 – 3 days!

Greenish water cloudiness

This is caused by floating algae, which make the water look greenish. This generally occurs more in ponds than in aquariums. For the aquarium a liquid anti-algae agent ( JBL Algol (Use biocides safely. Always read the label and product information before use. Registered at the Federal Institute for Occupational Safety and Health under BAUA number N-19236) ) or the use of a PROCRISTAL water clarifier ) are useful. The power (wattage) of the UVC water clarifier depends on the water volume of the aquarium.

Operating principle: The water inside the UV-C water clarifier flows relatively slowly along the germ-killing UV-C radiation. These kill off the floating algae.

Yellowish or bluish colouring

A colouring is mostly caused by medications (e.g. bluish colouring) or by phenolic substances, which occur during various degradation pathways (yellowish colouring). The use of activated carbon ( JBL Carbomec activ ) in the filter system provides the fastest help. Activated carbon binds dyes and thus creates clear water without a colour cast.

Brownish colouring

A brownish colour is often caused by humic acids that are dissolved out of peat or wood, for example. If the use of activated carbon ( JBL Carbomec activ ) does NOT help, you will either have to live with the brown tinge (it has no harmful effect!) or remove the piece of wood or try it with another piece of wood. Hard woods often cause little to no colouring compared to softer woods such as mangrove or bogwood.

Cloudy water in the aquarium

Find out in this video what types of cloudiness there are, why they occur and what you can do about them.

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