Marine water technology

Technical features of a marine aquarium

A special light, flow pumps, a chalk reactor and a protein skimmer are those technical items which distinguish a marine aquarium from a freshwater aquarium.


The water in marine aquariums needs a blue tone to look like the sea. That’s why we use cold light colours for the lighting, see Light . For fluorescent tubes you should combine a cold daylight tube (e.g. JBL SOLAR MARIN DAY T8 ) with a special blue tube (e.g. JBL SOLAR MARIN BLUE T8 ). Put the daylight tube at the FRONT above the fish and the blue tube over the background above the corals. Please also choose a LED light which creates cold light colours between 10,000 and 15,000 K. Metal halide lamps (HQI) create a suitable light but also an enormous amount of heat with high power consumption. Illuminate your aquarium as brightly as possible! The corals will thank you with beautiful growth. It is NOT useful to illuminate a marine aquarium ONLY with blue tubes! The corals don’t live in greater depth but mainly somewhere between the water surface and a depth of 30 m.


Almost all animals have accustomed themselves and adapted to the prevailing currents in the sea. You therefore need to simulate these currents with water pumps.

(Water) Pumps

The possible applications of water pumps in bio filters, as flow pumps and many other uses

Chalk reactors

Your corals (and the other animals) need larger amounts of calcium, magnesium and other trace elements for their growth. In your freshly prepared marine water these substances are available from the start but will then be consumed. You have only two options: you can supplement calcium etc., such as JBL CalciuMarin and JBL MagnesiuMarin or you can use a chalk reactor. Fill calcareous material (coral gravel, marble chips etc.) into the cylinder of the chalk reactor and let marine water run through it. Connect a CO2 system to the chalk reactor which reduces the pH level inside the reactor to about 6 by adding CO2. As soon as the pH value falls below 7 calcium components from the coral gravel/marble chips dissolve in the water and can be supplied to your aquarium water drop by drop. This is certainly the most elegant but also the more cost-intensive solution compared to JBL CalciuMarin .

Protein skimmers

The protein skimmer contains of a cylinder which is entered by your aquarium water. A pump or an air stone creates a lot of air bubbles inside the cylinder. If there is a water pollution in the form of protein compounds (from food, fish excrements etc.) the many air bubbles form foam which rises upwards in the cylinder. At the upper part of the cylinder is a collecting vessel for the foam. This way you elegantly remove the pollutants, BEFORE they can be biologically broken down in the aquarium. Now you just need to empty the foam collecting vessel regularly and to adjust the foam quantity properly every now and then. Disadvantage: protein skimmers don’t only remove pollutants but also valuable trace elements and vitamins.

Measurement of salt density (JBL hydrometer)

With the help of a floating spindle you can see how much salt is in your water. Most marine animals are comfortable with a density between 1.022 and 1.025. See thermometer .