Randy,
I was so proud of myself that I finally had carbon in a reactor. Since it's post ozone and I plan to run 24/7 how do I determine if I need a completely separate carbon reactor on another feed?
IMO, if you can smell ozone, there is a possible human safety concern.
If you can measure anything substantial with a chlorine kit on the effluent, there is not good enough contact with the water.
Here's what I found in my setup (copy and paste):
In order to assess the GAC's impact on the water, the water can be tested for ozone and ozone byproducts (
OPO's) before and after the GAC. Using my tubing reactor, with a water flow rate of about 0.5 gallons per minute, I found that the residual oxidant was 0.10 - 0.24 ppm chlorine equivalents before the activated carbon. After the activated carbon, the effluent had an oxidant level of 0.04 ppm chlorine equivalents or less.
When using the Coralife ozone reactor as the reaction chamber, the water flow rate was set to 0.44 gallons per minute, with an additional 0.05 gallons per minute of water in the air/water overflow. Both of these water streams were tested. I found 0.5 ppm chlorine equivalents in the air/water stream and 0.02 to 0.04 ppm chlorine equivalents in the primary water flow before the GAC. The combined flow therefore would have a level of about 0.09 ppm chlorine equivalents. After the activated carbon, no oxidant could be detected (<0.02 ppm chlorine equivalents).
Clearly, the GAC is doing a good job of reducing the highly oxidizing species present in the water. In some tests it was not perfect, but I believe that these levels (< 0.04 ppm chlorine equivalents) are acceptable. Interestingly, the GAC does not greatly lower the ORP. The ORP before the activated carbon was 680 mV after 5-15 hours of equilibration, and was 670 mV after 8 hours of equilibration in the post activated carbon effluent. Consequently, the effluent's ORP is not a suitable way to measure whether the activated carbon is effectively removing residual ozone and its byproducts.
