On Thursday, we visited Morava river basin, their laboratories and we tried to measure samples of water and also observed macrozoobentos. After lunch we enjoyd Aqualand Moravia with short stop at "Novomlýnské reservoir". 

Water pollution can be determined by various chemical, biological and physiological methods, but they are often expensive and require extensive knowledge. However, there is one biological method that is simple, comprehensive and quick and that many can easily use, based on the observation of the animals themselves. 
Animals are present in the water at all times so any water pollution will affect them. Any longer and more significant change in water quality results in a change in the composition of the animals that reside in it, that is, animals that are highly sensitive to pollution will disappear and will be replaced by those that are less sensitive. 
Pollution-sensitive animals (for example, larvae of stoneflies (Plecoptera) and more nymphs of mayflies (Ephemeroptera)) have a high number (for example 10 points), while animals that tolerate pollution (for example Oligochaetes and light flies (Chironomidae)) have a lower numerical value. (for example 1, 2, or 3 points).