Osnabrueck zoo tests Tetra BalanceBalls

Here at Tetra, we have been supporting the aquarium at Osnabrück Zoo for many years. As part of this cooperation, we supply aquarium manager Stefan Bramkamp and his team with a broad range of Tetra food products, including TetraMin Flakes, TetraMin Granules and TetraMin Crisps, as well as multiple care products such as Tetra EasyBalance and Tetra SafeStart along with water tests. With water care products in particular, it is always exciting for us to see how these fair in large-scale aquariums such as the one at Osnabrück Zoo. 

Tetra BalanceBalls in the axolotl tank 

In June 2015, aquarium manager Stefan Bramkamp placed the Tetra BalanceBalls in the axolotl tank’s filter system. The BalanceBalls are made of a special water-insoluble polymer, which serves as a nutrient for nitrate-reducing bacteria and supports the formation of a biofilm on which the denitrifiers settle. The balls also ensure constant optimum water quality parameters. This is because, when the nitrate is broken down, not only is the eutrophying nitrogen removed from the water, but the carbonate hardness (KH) and thus the pH level are also stabilised. These two closely related water parameters play an important role in maintaining a healthy ecosystem. Minor fluctuations over the course of the day are quite normal both in the wild and in the aquarium.

KH and pH-level fluctuations

Despite minor fluctuations being normal, major ones can be problematic or even fatal for the aquarium inhabitants. This is true if the pH level drifts into the acid range or in the dreaded case of a sudden drop in acidity, as well as conversely, if extreme alkaline values occur. With fish, we even talk of acidosis or alkalosis, which leads to major gill and breathing problems.

But these extreme water quality parameters also affect the microbiology, for example by restricting or even damaging the essential activity of the filter bacteria (nitrifiers). The Tetra BalanceBalls stabilise the water's carbonate hardness at a pre-set level determined by the aquarist. This means that the balls have intentionally been designed not to function in the same way as products that are specifically used to rapidly increase the carbonate hardness level.

Stable water quality parameters 

It was this aspect that made the use of Tetra BalanceBalls at the zoo particularly interesting. After all, it is hard work achieving a stable environment or stable water quality parameters in an axolotl tank: The animals are only fed every four to five days and, on feeding days, an intermittent surplus of nutrients subsequently occurs due to the excretions.

The biological filtration performance also varies considerably with the changes to the pH level – making it extremely difficult to achieve a permanently stable environment in the water. However, by using Tetra BalanceBalls, these problems are now a thing of the past. Stefan Bramkamp stated: “In terms of stable water quality parameters, the BalanceBalls have been extremely effective. The water quality parameters are now at a consistently good level, which makes looking after the axolotl far easier. What a fantastic result!”

© Tetra
BalanceBalls effectively break down nitrate 

The primary role of the Tetra BalanceBalls is to break down nitrate. As the water for the zoo’s aquaria is prepared with an osmosis system, it generally contains very little nitrate. Nevertheless, nitrate has clearly been broken down with the aid of the BalanceBalls as, after around five months, they are almost completely used up, proving that denitrification has taken place.

In addition, the recorded stabilisation of the water quality parameters is only possible in connection with denitrification. “Incidentally, the water quality parameters are still remaining stable even though there are only a few remnants of the BalanceBalls left in the filter”, says Stefan Bramkamp. “To maintain this healthy environment in the aquarium, we’ll now top up the Tetra BalanceBalls again.”

AUTHOR: Tetra GmbH
DATE: 12.05.2016