In your post they state that it removes organics that decay into nitrogenous waste, not nitrate. However, I was incorrect in stating that it removes ammonia and nitrite. And you guessed right, it was in Q & A. But it was just the first link when I googled "does purigen remove nitrate"?
This is directly from SeaChem:
"Hello,
As you said, Purigen will remove the organics before they are converted into the toxic nitrogenous components.
.It is a specific scavenging resin that will target the organics that your fish produce, however it is impossible to measure how much waste is in the tank and how much it removes; it depends on your bioload, size, water parameters, etc. Purigen works extremely efficiently and should remove all the organics that it comes in contact with; it will continue to remove these organics until it is exhausted (noted by a dark brown color).
There are no products on the market that directly removes nitrate (or nitrite and ammonia). Purigen will prevent your nitrate levels from increasing any higher than they were before placing it in your tank (i.e. if your nitrates were at 10 ppm before you placed Purigen in the tank, once you place it in your tank it will not exceed 10 ppm from there on out). Prime binds to the nitrates and renders them nontoxic to your fish while allowing your bacteria to consume them. Prime can safely be used in a double dose every 2 days to help with nitrates (the 5x dose is recommended for nitrites, not nitrates), and again, the amount it helps remove will be dependent on your biological filter. Your test may still register as having nitrates present, but that is because there is no test that can distinguish between free (toxic) and bound (non-toxic) nitrate.
The only way you will remove nitrates in your aquarium is through your bacterial filter and/or water changes.
Our products Stability and Matrix are suggested to be used in conjunction to help attack the nitrogenous waste problems aquarium owners encounter. Stability is a unique blend of bacterial supplements designed to add both the aerobic and anaerobic bacteria directly into your tank. Matrix affords the bacteria the chance to grow in both an aerobic and anaerobic environment while maintaining water flow. Adequate water flow can be a problem when only using a deep sand bed.
Thanks again for your post and have a great day!"
So perhaps your nitrate reduction was due to a population of denitrifying bacteria. They live in almost every system to some degree.
Never lost a fish. I do make sure I do add around 20% back from 5 gallon buckets to keep the desired temp and then just hook the hose up to the fascist and test to see if the temps match up by hand and let it fill so even if the temp doesnt match perfectly its only off by a couple degrees worst case scenario.
