The city where I live is adding an extreme amount phosphate to the water due to its purification process. The RODI can not even filter all of this out. Does anyone have any thoughts on using a water delivery service or buying bottled water.
High Phosphate even after RODI filtering
- Thread starter Ljmiller
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I find this very hard to believe. Any good RO/DI with the correct membrane and DI resin is more than capable of removing orthophosphates at EPA approved levels.
What makes you think you have phosphates in your treated water? What RO/DI do you have, are you using fresh resin in a vertical 20oz cartridge and what are you testing with?
What makes you think you have phosphates in your treated water? What RO/DI do you have, are you using fresh resin in a vertical 20oz cartridge and what are you testing with?
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My Tank Thread
If the amount left in the RO/DI is on the order of 0.1 ppm or less, it may sound concerning, but that level is unimportant to the phosphate balance of a typical reef since you add tens to hundreds of times that much each day with foods.
I discuss it here:
http://www.advancedaquarist.com/2012/3/chemistry
from it:
Comparison of Food Sources of Phosphate to Other Sources
What about other sources of phosphate, like the "crappy" RO/DI water containing 0.05 ppm phosphate? A similar analysis will show it equally unimportant relative to foods.
Let's assume that the aquarist in question adds 1% of the total tank volume each day with RO/DI to replace evaporation. Simple math shows that the 0.05 ppm in the RO/DI becomes 0.0005 ppm added each day to the phosphate concentration in the aquarium. That dilution step is critical, taking a scary number like 0.05 ppm down to an almost meaningless 0.0005 ppm daily addition. Since that 0.0005 ppm is 40-600 times lower than the amount added each day in foods (Table 4), it does not seem worthy of the angst many aquarists put on such measurements. That said, tap water could have as much as 5 ppm phosphate, and that value could then become a dominating source of phosphate and would be quite problematic. Purifying tap water is important for this and many other reasons.
I discuss it here:
http://www.advancedaquarist.com/2012/3/chemistry
from it:
Comparison of Food Sources of Phosphate to Other Sources
What about other sources of phosphate, like the "crappy" RO/DI water containing 0.05 ppm phosphate? A similar analysis will show it equally unimportant relative to foods.
Let's assume that the aquarist in question adds 1% of the total tank volume each day with RO/DI to replace evaporation. Simple math shows that the 0.05 ppm in the RO/DI becomes 0.0005 ppm added each day to the phosphate concentration in the aquarium. That dilution step is critical, taking a scary number like 0.05 ppm down to an almost meaningless 0.0005 ppm daily addition. Since that 0.0005 ppm is 40-600 times lower than the amount added each day in foods (Table 4), it does not seem worthy of the angst many aquarists put on such measurements. That said, tap water could have as much as 5 ppm phosphate, and that value could then become a dominating source of phosphate and would be quite problematic. Purifying tap water is important for this and many other reasons.
Well, I finally found the reason why I am cleaning the glass this much. Tracing the phos. Backwards from tank water to Ato, then Rodi container, output and finally tap water. Here is tap water;
Hanna ultra Checker blinks at 200. Indicating it is over 200. Color looks like 350-400 to me. The order is 1 Micron, carbon, membrane, resin. Output value is 50 ppb. 1micron and resin just changed. Today I added another container of resin and now the value is 40 ppb. Whats missing here?
Hanna ultra Checker blinks at 200. Indicating it is over 200. Color looks like 350-400 to me. The order is 1 Micron, carbon, membrane, resin. Output value is 50 ppb. 1micron and resin just changed. Today I added another container of resin and now the value is 40 ppb. Whats missing here?
