OK... I've bit my tongue long enough, but everyone repeating the mantra "ditch the biowheel" doesn't do any good if we don't know what the person's system consists of.
If a person has a ton of live rock and live sand, then yes... the biowheel isn't doing them anything beneficial when it comes to biological filtration. Is it a guaranteed "nitrate factory"? Maybe... maybe not. More on that later.
But if a person has no live rock, or very little, that biowheel might be the only thing in their tank that's providing biological filtration. And removing it would crash the tank. In that situation, yes... it does lead to high nitrates because that's what it's supposed to do - convert ammonia/nitrite to nitrates. The high phosphate thing is a new twist - can't see how it would increase those. Phosphates aren't generated in your tank - they're just there through water, food, or poor quality carbon.
If I've missed somewhere what Social_d87 has in their tank for biological filtration, then I apologize. But it's times like these that it'd sure be nice to have that "My Info" feature back. (Hint hint to the admins.)
Biowheels get a bad reputation, I believe, because they're like a wet/dry filter in that they're just too efficient in converting ammonia and nitrites to nitrates! That, and if you don't maintain the filter pad before the biowheel by rinsing it out AT LEAST weekly in salt water, will cause your tank to create nitrates pretty fast. Any foam filter anywhere that collects uneaten food, fish waste, etc, and lets it rot away is going to create nitrates.
If you have adequate live rock, then you really don't need a biowheel. It's pointless. Unless you're using it to give yourself the ability to take it off the main tank and set it up on a quarantine tank to make a tank instantly ready for fish. I use one on my 46g for that reason. And if you use one in that way, you need to maintain it or it will generate nitrates - but it's not the biowheel itself that's doing it!