Due to the pandemic, I've been unable to do water changes in my new saltwater tank. I've been topping off with rainwater just to make up for evaporation. Parameters as seen below are in keeping with what they have been so far. Nitrates were initially stable at 5ppm but took a drop to nearly undetectable after some cyano and have remained low since. Phosphates have always been 0.25 since day 1 no matter what. Even after water changes they do not decrease. Strangely enough in the 2-3 week period I have done no water changes phosphates have not increased at all.
I just got a RODI system and did basically a 100% water change yesterday. HOWEVER, phosphates are still at 0.25ppm. Salt mix using rodi didn't have phosphates. Is there a magical phosphate fairy dosing my tank at night or something? Strangely enough my salt mixed to pH 8.4 Alk 8 but after 1 night pH dropped to 8.09 and Alk to 7.5. Considering I don't have SPS or LPS and only very small patch of coralline on a frag plug I find that strange as well.
By far the most worrying of all these parameters are the phosphates which will not rise or fall from 0.25. It's almost as if there is something trying to keep that level in equilibrium. It honestly is amazing after doing an almost 100% water change phosphate would re-stabilize to 0.25 in one night. So the million dollar question is... Why are my phosphates always high (but never increasing)??
Tank size 20 Gallons (15 accounting for rock and substrate)
Salinity 1.024
pH 8.09
Alk 7.5
Ammonia 0
Nitrite 0
Nitrate <5
Phosphate 0.25
Salt mix Fritz pro mix
Tank is 2 months old. Started with dry rock. Stocked with 2 clowns, 1 royal gramma, 1 cleaner shrimp,1 feather duster. Only coral is pulsing Xenia. Protein skimmer and HOB filter (filter pad contains some carbon)
I just got a RODI system and did basically a 100% water change yesterday. HOWEVER, phosphates are still at 0.25ppm. Salt mix using rodi didn't have phosphates. Is there a magical phosphate fairy dosing my tank at night or something? Strangely enough my salt mixed to pH 8.4 Alk 8 but after 1 night pH dropped to 8.09 and Alk to 7.5. Considering I don't have SPS or LPS and only very small patch of coralline on a frag plug I find that strange as well.
By far the most worrying of all these parameters are the phosphates which will not rise or fall from 0.25. It's almost as if there is something trying to keep that level in equilibrium. It honestly is amazing after doing an almost 100% water change phosphate would re-stabilize to 0.25 in one night. So the million dollar question is... Why are my phosphates always high (but never increasing)??
Tank size 20 Gallons (15 accounting for rock and substrate)
Salinity 1.024
pH 8.09
Alk 7.5
Ammonia 0
Nitrite 0
Nitrate <5
Phosphate 0.25
Salt mix Fritz pro mix
Tank is 2 months old. Started with dry rock. Stocked with 2 clowns, 1 royal gramma, 1 cleaner shrimp,1 feather duster. Only coral is pulsing Xenia. Protein skimmer and HOB filter (filter pad contains some carbon)