Correction for Later editions of Aquaresp 2

A bug in the file saving, as resulted in MO2’s for channels 2,3,4 in multiple chamber setups has been calculated with the mass of the animal in chamber 1. This is ONLY affecting the chambers 2,3 and 4. Thank you to Denis Chabot for bringing this to attention.

I am sorry for any inconvenience this may have caused. The error is fixed in the presently (December 21, 2015) available version of Aquaresp 2.

To correct for this use the following formula on the MO2’s from the chamber “n”


correction formula

correction formula


In order to calculate MO2 from the determined slopes , alpha, the following formula should be used.

Formula MO2 respirometry

MO2 formula

Where Beta is oxygen solubility in mg / l, V is the effective respirometer volume and ma is the animal mass.


It is suggested to always calculate the MO2 after experimentation using automated respirometry in e.g. Excel order to validate results and to correct for possible changes in fish mass or temperature during the experiment. (Yes, also when using the commercially licensed Loligo Systems setup). For more information, please read “Design and setup of intermittent flow respirometry systems for aquatic organisms




Oxyguard electrodes requires different electrolytes

Electrolyte for different Oxyguard Electrodes:

If you are using the Oxygen oxygen electrodes, be aware that they use different electrolytes


Handy Polaris has an anode made of zinc and for this you should use type 1 electrolyte.

Model D16 Mini DO has an anode made of lead and for this probe you should use type 2 electrolyte.

Model 420 has an anode made of iron and for this probe you should use type 3 electrolyte.


One of the Oxyguard electrolytes can be made like this – type X ??:

238 g KCl + 900 ml dist. Water + 100 ml Glycerine


If somebody know how to make the other electrolytes please tell us and we will update the info.