My tapwater contains high levels of phosphates i.e., 1.5mg/L Ortho phosphate.
Can a Kold Ster-il® remove the phosphates & silicates sufficiently to be
able to keep aquaria free of excessive algae or diatom growth?
My tapwater shows low levels of Ortho phosphate and silicates
but my reef tanks have excessive algae growth.

The Kold Ster-il® sorbs ortho phosphate + hydrolyzable phosphates + other organic bound phosphates. The 0.20µm filter bag found in the second canister will completely restrict particulate phosphates found in many types of surface water supplies. Under optimum conditions, standard Kold Ster-il® can produce filtrate containing 0.100mg/L total phosphates. If Phosphate is the major problem occurring in your water supply, we recommend slowing intake water flow down to 1-2 liters per minute. Another solution is add 1 pound of our special activated alumina to the 0.20 micron filter bag. Difficult mixing of synthetic salts (brown floc or plating) means phosphate based charged polymer water conditioners or hexa-meta, poly, tripoly phosphates (1.0-2.0 mg/L concentration) added as a corrosion or heavy metals inhibitor. We suggest a Kold Ster-il® system with our activated alumina complex. This will sorb the phosphate complex + any bonded heavy metals. Both hexa-meta and poly phosphates must be determined via hot acid digestion which converts the complexed phosphorus over into a detectable ortho phosphate. As an additional benefit silicates are fully sorbed along with the various inorganic and organic phosphates.