Randy Holmes-Farley
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My Tank Thread
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Hi Randy. M friend is having major grenn hair algae issues, with nitrates at 0 and phosphate at 1.72, as tested on a hanna checker. His ro system is delivering 0ppm tds. The ro water itself gets a phosphate reading of 0.23 and after mixing the saltwater the phosphate reading is at 0.43. Do you think these readings indicate that the source water might be a problem and should be addressed, or do you think because his current tank phosphate is 1.72 that we should be looking elsewhere for the phosphate problem?
The source water is not the main source of phosphate for that tank, but is a substantial source. Foods are a bigger source.
Lowering the phosphate will take effort, even if you cut off the Ro/DI source, but keep in mind that algae will grow equally well at 0.2 ppm and 1.7 ppm phosphate. More and more of any needed nutrient does not necessarily make algae grow faster and faster, because something else becomes limiting (in this case it may weell be a source of nitrogen (N).