Water samples were taken from the centre of the aquarium tanks. Measurements of nutrients were conducted photometrically using the photometer Merck Nova 60 Spectroquant and the respective test kits Merck Spectroquant: Phosphate Test 1.14848.0001, Ammonium Test 1.14752.0001, Nitrate Test 1.14942.0001, Nitrite Test 1.14776.0001;Measurement of Carbonate hardness ( °dKH ) were conducted with Test kit Merck 1.11103.0001The pH of the aquarium water was measured with the pH-meter WTW pH 3310, pH probe WTW SenTix 81Conductivity meter: WTW Cond 3110, probe : TetraCon 325Oxygen was measured with a YSI Pro ODO meter.