Questions regarding Kessil to Apex cable and programming for ATO


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Nov 27, 2018
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Richmond, Virginia

I've had my Apex for awhile but have really only used it as a temp controller and pH control if my ATO goes bonkers.

I've had my A360WEs being controlled by the Kessil spectral controller but want to switch it to the Apex. Kessil wants $20 for the cord but it just looks like a male audio plug and an RJ45. There are similar cables/adaptors on Amazon for Like, $4. Can I use these or is there something different about the Kessil cable?

Also, similar to how there is a task that sets the Skimmer to stay off for 5minutes after the return pump cuts back on, I want to make it so my ATO doesn't cut on for 5-10 minutes after the return pump comes back on.

Reason being is it takes a few minutes for the water levels in the sump to balance out and sometimes the ATO cuts on needlessly lowering salinity.

Thanks so much, this community as well as R2R as a whole have been super helpful throughout the years.


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May 10, 2020
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New York
pins on and 2 are one channel pins 5 and 6 are the other pins one and 5 are positive pins 2 and 6 are the negative.
you can connect a standard audio jack to each pair. the negativ will be on the ring of the jack and the positive will be on the two terminals closer to the tip. one channel will do dimming i think the other can do the color.

here's a diagram using led drivers.

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