Well I just walked into my hot water tank exhaust taking pictures and burned my forehead wow ha ha .
Turns out while producing its hard to see water In The Di housing
What's your tds reading? As a side note did u remember to install the flow restriction I have about 4 of these on my tanks and friends tanks and its easy to miss.
Great unit you got tho
Not sure if these will help and but this is the side that was up on my canister disregard the fact it's broke

Full
Producing water

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360 gallon sps reef, 180 gal sump, bubble king supermarine 300, 4xmp40Wes, 2 x 6215 tunze waveboxes, 4 ghl mitras
360 Reef Tank