ELOS AQUA TEST KIT- PH FRESHWATER The ph-value or acid value indicates how acidic or alkaline the water is. It is the measure of the concentration of the acidic or alkaline components in a hydrous solution. Pure water will react neutral and has a pH value of 7.0. If the acidic components are predominant, the pH value will drop below 7.0. If the basic components are predominate, the pH value will rise above 7.0. In freshwater aquariums, when not dedicated to Malawi cichlids etc., the optimum pH value is between 6.2 and 7.2 which are found in natural water. Many organisms are very sensitivity to large variations of the pH-value, so large swings should be avoided. ELOS AquaTest pHD, as well as all the other colorimetric test kit of this line, grant very high precision thanks to several procedures like the use of “RealColor” technology, an accurate system to calibrate the color chart compared to the reagents; the validation of each reagent with NIST (National Institute of Standard and Technology) certified samples and the careful stock management to supply to our customers ONLY the freshest production batch. HIGHLIGHTS: * Easyreading: “RealColor”technology. * High precision: thanks to the use of calibrated droppers * NISTvalidation: each batch of elos reagents is validated using NIST(National Instituteof Standardand Technology)samples * "Safe reagents": reagents and testing procedures are based on Low Risk Reagents. None of our test kits are based on Toxic Reagents.