Majjie
Fishaholic
I bought a phosphate test kit when I was in my lfs at the weekend - I don't know why - just my everlasting quest for knowledge I guess 
I also bought a new nitrate test kit - I don't just study the test kits for fun - honest
So, today, I've tested the four tanks in my living room. The water in one of them has had several small water changes over the last week or so, one has regular weekly 20% water changes, one hasn't had any water changed for two weeks and the last had a massive 80% water change and a good clear out yesterday (I kept the fish and the filter in the 20% that was put back in).
All had relatively low nitrate levels, between 12.5 and 25 mg/l (which I have in my tap water anyway) but to my surprise all had more than 5mg/l phosphate (the highest level of the test). My tap water doesn't have a detectable PO4 level.
So, two questions:
How come they all had the same level of PO4 in spite of the different water changes?
I've developed my water change schedules to keep the nitrates low - given that my tanks are quite highly stocked. So, should I worry about the PO4 levels?
(They're low tech planted tanks, pH levels are between 7 and 8 and I only had a real algae problem in one tank which gets the sun - which I solved by adding six Amano shrimp)
I also bought a new nitrate test kit - I don't just study the test kits for fun - honest
So, today, I've tested the four tanks in my living room. The water in one of them has had several small water changes over the last week or so, one has regular weekly 20% water changes, one hasn't had any water changed for two weeks and the last had a massive 80% water change and a good clear out yesterday (I kept the fish and the filter in the 20% that was put back in).
All had relatively low nitrate levels, between 12.5 and 25 mg/l (which I have in my tap water anyway) but to my surprise all had more than 5mg/l phosphate (the highest level of the test). My tap water doesn't have a detectable PO4 level.
So, two questions:
How come they all had the same level of PO4 in spite of the different water changes?
I've developed my water change schedules to keep the nitrates low - given that my tanks are quite highly stocked. So, should I worry about the PO4 levels?
(They're low tech planted tanks, pH levels are between 7 and 8 and I only had a real algae problem in one tank which gets the sun - which I solved by adding six Amano shrimp)
