Excused… no problem.
Just wondering… in your opinion, why do you chill reservoir water and who told you that? And, at what temperature does cold water (hypothermia) begin to suppress root and beneficial microbe metabolism? Hypothermia definitely compromises and retards metabolism guaranteed to slow root and Benny growth. Why would you want to do that?
This is the cheapest way to I have found to test and measure DO. Each DO test only cost about $0.50 - *Salifert Dissolved Oxygen Test Kit – $22.31 + ***FREE SHIPPING --
https://www.amazon.com/dp/B001EJ3DQ4/?tag=skimlinks_replacement-20
EC and pH testing is popular, cheap and common for DWC growers and most people know what to do if these test results are not within the “safe range.” Most growers react and implement corrective measures to get pH and EC back within the “safe range.” That is logical, ya.
But, what in the world would you do if you did a $0.50 DO test on your nutrient water and discovered that your DO saturation was not even close to 100% saturation and was only 50% - 60% DO saturated? Your water is cold and your air pump and bubblers are making millions of bubbles. This is far from the ideal 100% saturation which is considered “safe oxygenation?” What DO is do you considered unsafe or “low dissolved oxygen” conditions?
Would you do anything or just wait and tither about looking into the crystal ball and know what’s coming? Doing nothing about correcting a low DO back to the “safe DO range” is not even close to logical, but that is always the growers choice and responsibility to keep his crop healthy.
I have also heard that ignorance can be bliss. Sometimes it’s less stressful not to know what’s coming next when you know your nutrient DO is deadly low. Like knowing how long you have left to live and getting past denial to acceptance.