0 po4 in a few month old tank seems rather strange to me. what po4 test did you use? some are far from accurate at low range tests

I think it's salifert. All my tests are salifert or seachem. I'll have to check next time I go into the fish cave

When I first test the tank when it was initially set up I was getting some reading but now I am getting nothing...

And yes, my skimmer is hauling stuff out.. Not much though LOL