I just put some in the Two Little Fish reactor I bought. How long does it last in my 72 bow front? I have 100 lbs. of live rock, and 70 lbs. of live sand. Thank you.
Jesse, each tank is going to need changing at differing intervals. There are various factors that will deplete the effectiveness of the Phosban at different rates. How heavily stocked your tank is, what size the tank is, how much media you're using in the reactor, how fast/slow your flow rate through the media is, what type of food you're feeding, etc. I mention food because there are some frozen foods that seem to have higher levels of phosphates in them than other frozen and dry foods. Many people 'rinse' their frozen foods to remove phosphates before they feed their tank with it (I do.....and I notice a big difference).
So bottom line is, like Dean said, when your phosphates begin to rise it's time to change it.
What criteria are you using to say it is a better media?
While it does remove more phosphate per volume of media, it is more expensive. I also found that it was very dirty.
A while back, I tried and tested Rowa, Phosban, and PhoSar, measuring the amount of phosphate that was removed by each media with a Hanna Meter. The Rowa and the Phosban where almost interchangeable in terms of cost per unit of phosphate removed. The PhoSar removed as much phosphate as the Phosban when measuring Equal volumes of media, but cost significantly less.