Straight answers about pools, hot tubs and keeping them running
Pools Shop Editorial Team 
Calcium hardness matters because it controls whether pool water pulls calcium out of plaster, grout and equipment (when it’s too low) or deposits scale onto surfaces and clogs plumbing (when it’s too high). Keeping it in a reasonable range protects the pool’s finish and its circulation system over time. What is calcium hardness, exactly? Calcium … Read more
Total alkalinity measures how much dissolved mineral buffer is in the water — mainly bicarbonates — while pH measures how acidic or basic the water actually is right now. Alkalinity is the water’s resistance to pH change; pH is the reading that resistance is protecting. They move together, but they answer different questions. What does … Read more
pH is a measure of how acidic or basic pool water is, on a scale most pools are tested against between roughly 7.2 and 7.8. It matters because pH controls how well chlorine works, how comfortable the water feels, and how much it corrodes or scales pool surfaces and equipment. What does pH actually measure? … Read more
Free chlorine is the sanitizer that is still available to kill germs and control algae. Combined chlorine is chlorine that has already reacted with contaminants and lost most of its sanitizing power. Total chlorine is simply free plus combined added together — it tells you what’s there, not how much is still working. Understanding the … Read more
Chlorine’s job in a pool is to kill bacteria, viruses and algae, and to break down organic waste like sweat, urine and sunscreen before it builds up. It does this through a chemical reaction, not by “cleaning” water the way a filter does — chlorine and filtration are two separate, equally necessary jobs. What is … Read more
Clear pool water comes from three things working together: filtration that physically removes particles, circulation that moves every gallon past that filter regularly, and balanced chemistry that keeps contaminants dissolved or destroyed instead of clouding the water. Skip any one of the three and the water dulls, no matter how much chlorine gets added. Why … Read more
Why Does Pool Water Go Cloudy? Pool water goes cloudy when tiny particles — dust, body oils, algae cells, or mineral residue — stay suspended in the water instead of settling out or being filtered away. That usually points to one of four things: weak filtration, poor circulation, unbalanced chemistry, or an early algae bloom. … Read more
A pool’s equipment pad is the concrete or gravel area, usually tucked against a wall or fence, where the pump, filter, and often the heater and automation gear all sit together. It’s the mechanical heart of the pool — everything that moves, cleans, and heats the water lives there, connected by a maze of PVC … Read more
Evaporation drops a pool’s water level slowly and evenly, usually a small amount every day, faster in hot, dry or windy weather. A real leak tends to lose water faster than weather alone can explain, keeps dropping even when the pool isn’t running, or shows up alongside wet spots, soggy ground or a rising water … Read more
Pools lose water without any leak mainly through evaporation, splash-out from swimmers, and backwashing the filter. On a hot, windy, or low-humidity day, an uncovered pool can lose a noticeable inch or more a week from evaporation alone — no cracked pipe or liner tear required. Is it normal for a pool to lose water? … Read more
About what you read here. Everything on Pools Shop is general information and our own editorial opinion. We research carefully and we say when the evidence is unclear, but we can be wrong, things change, and no article can know your particular situation. Please do your own research and make your own judgement rather than treating anything here as the final word. Prices, products and specifications around pools, hot tubs and their upkeep change constantly, and what suits one person will not suit another. Check current details yourself, and where a decision involves real money, safety or something you cannot undo, it is worth confirming with a qualified pool or electrical professional before you act.