My 150g very lightly stocked tank (6 fish and few inverts) is a little over a year old and has never really thrived. While most of the parameters have been fine (Temp: 80, Salinity: 35, Alk: 8.5, Cal: 480, Mag: 1510) I've historically struggled with my pH, Nitrates & Phosphates, and predictably I have had algae issues due to the nitrate & phosphate problem. I dosed NoPox for a number of months which did help with the nitrates---those are currently around 10---however, it really didn't seem to affect my phosphate levels, which never seem to be able to get below .1 on my Hanna ULR checker and left unchecked will approach .25 or more. I also run 2 BRS media reactors (one with GFO and one with RowaPhos) which don't seem to do a thing. I also do twice a month 15% water changes.
The only thing that has ever had an effect on my phosphate levels is Phosphate-e (lanthanum chloride) which does seem to work...but only for a very short time. For example, yesterday morning, my phosphate level was .17 so I dosed around 70ml of Phosphate-e. In the evening, my phosphate level was .11, however, by this morning it was back up to .19. So I just never seem to get ahead of it. Note also that I feed BRS pellets very lightly with an auto-feeder so I don't really think that's the source of the problem and my tank and ATS are sourced from a BRS RO system. I know that others have reportedly run great tanks with higher phosphate levels, however, I have significant algae levels which I strongly suspect are related to this so I'd like to address it.
I've heard that phosphate can "leach out of rocks" which could be a source. One thing that I'm wondering though based on some research here is the relationship between pH, phosphate and the Aragonite base (~1.5") that I have in my tank. My pH has pretty consistently been low (around 7.7) which I've never "chased", however, I've heard that a lower pH like that can leach out phosphate somehow from Aragonite? Could that possibly be my problem? If so, what would you guys recommend as a fix?
The only thing that has ever had an effect on my phosphate levels is Phosphate-e (lanthanum chloride) which does seem to work...but only for a very short time. For example, yesterday morning, my phosphate level was .17 so I dosed around 70ml of Phosphate-e. In the evening, my phosphate level was .11, however, by this morning it was back up to .19. So I just never seem to get ahead of it. Note also that I feed BRS pellets very lightly with an auto-feeder so I don't really think that's the source of the problem and my tank and ATS are sourced from a BRS RO system. I know that others have reportedly run great tanks with higher phosphate levels, however, I have significant algae levels which I strongly suspect are related to this so I'd like to address it.
I've heard that phosphate can "leach out of rocks" which could be a source. One thing that I'm wondering though based on some research here is the relationship between pH, phosphate and the Aragonite base (~1.5") that I have in my tank. My pH has pretty consistently been low (around 7.7) which I've never "chased", however, I've heard that a lower pH like that can leach out phosphate somehow from Aragonite? Could that possibly be my problem? If so, what would you guys recommend as a fix?