Fred Schweer Explains PoolRx Compatibility

Pool algae problems often get blamed on the newest product added to the water, but the root cause is usually basic pool water chemistry and setup. In our conversation with Fred Square from PoolRx, we dig into why a mineral-based chlorine enhancer can underperform when it is undersized, installed poorly, or paired with a dirty filter. The big takeaway for pool owners and pool service pros is simple: start with the fundamentals. Confirm gallons so the PoolRx size matches the pool, keep a free chlorine residual, and make sure filtration is working. If a pool is already struggling, adding minerals without addressing circulation, cleaning, and balanced ranges sets you up for disappointment.  

Installation details matter more than most people expect, especially when different filter types change how fast minerals dissolve. With DE filters, Fred recommends breaking down and recharging grids correctly, and placing the unit in the skimmer farthest from the pump to improve dissolution, or using a bypass if available so minerals do not get trapped in the DE media. With sand filters and cartridge filters, the pump basket is often the easiest and most effective spot because all water passes through it. A practical tip that saves headaches: tell customers the unit is supposed to be there so it does not get thrown away during a skimmer cleanout. For new installs, run the pump long enough so minerals dissolve steadily instead of pooling in the basket and blasting through later as a concentrated blue cloud.  

A major theme is what happens to minerals over time and why “metal fear” needs context. PoolRx uses chelated minerals, which helps keep them protected and effective through the product lifespan. Those minerals get used up and ultimately get filtered out, which is why routine filter cleaning matters. The staining stories that circulate in the industry often point to something else: existing metals already present before PoolRx goes in. Iron can show up as brown staining, while copper can appear as dark or purple-toned marks, and shocking the pool can make those stains suddenly visible because oxidation is more aggressive. If you fill from well water, have old copper plumbing, or suspect a worn heat exchanger, testing for metals at least annually is smart whether you use PoolRx or not.  

When metals are present, the recommended workflow is test first, remove what you can, then install. Fred mentions products like a metal-removal bag that physically traps trace metals in the skimmer or pump basket, unlike liquid sequestrants that mainly keep metals in solution. Higher flow over the bag can shorten the cleanup window dramatically. Another key nuance: once PoolRx is in the water, copper testing can look inconsistent because strong chelation interferes with common reagents, including some advanced testing methods. That is why a pre-install copper level check is the meaningful number. Ongoing maintenance becomes observation-based: rising chlorine demand, cloudiness, or any hint of algae can signal it is time for a booster rather than guessing from unreliable metal readings.  

Compatibility questions come up constantly, and the guidance is straightforward for most modern pools. PoolRx is compatible with borates, enzymes, phosphate removers, UV, ozone, AOP systems, salt systems, and typical chlorine programs, but the conversation highlights cautions around mixing metals, bromine systems, and biguanides. Cal hypo shock is allowed, yet application technique matters: dissolve and dilute in a bucket, then pour into the deep end to avoid localized “flash” oxidation and temporary black spotting on surfaces. For pool pros, that mix of simple install steps, fewer algae callbacks, and an easy physical product to show the customer can make PoolRx an easy-to-sell add-on, as long as you lead with education and clean, repeatable process.