Pharomones

That’s a great follow-up question. The interaction between chlorine and other common substances in a hot tub is a key part of water chemistry, and it’s what often leads to the issues people complain about.Here is a breakdown of how chlorine interacts with body oils, sweat, and cosmetics and the important byproducts that are created:1. The Interaction with Oils, Sweat, and UrineThe body introduces a high concentration of organic matter into hot tub water, especially since the hot temperature causes faster perspiration and opening of pores.| Contaminant Source | Chemical Components | Chlorine Reaction ||—|—|—|| Sweat & Urine | Urea, Ammonia, Nitrogen compounds | Chlorine is consumed as it reacts with ammonia/nitrogen compounds. || Body Oils | Lipids, Waxes, Fatty Acids | Chlorine oxidizes (breaks down) these compounds, but they can be slow to react and may float as a scum line. || Dead Skin Cells | Organic matter | Chlorine oxidizes the cells, consuming the free chlorine sanitizer. |2. The Formation of Chloramines (Combined Chlorine)This is the most significant byproduct and the main issue with hot tub chemistry: * What are Chloramines? They are chemical compounds formed when Free Chlorine (the active, working disinfectant) binds with Nitrogen-based compounds (like ammonia from sweat and urine). They are also known as Combined Chlorine.

* The “Chlorine Smell”:

Ironically, the strong, irritating “chlorine smell” in a hot tub or pool is not caused by too much effective chlorine, but by too many chloramines. It’s a sign that the free chlorine has been used up and the water is actually poorly sanitized. * Irritation: Chloramines are highly irritating to the eyes, skin, and respiratory system. They are the primary cause of red, stinging eyes and dry, itchy skin after a soak.

* Poor Disinfectant:

Chloramines are much less effective at killing bacteria than Free Chlorine. As they build up, they deplete your available sanitizer, making the hot tub less safe.3. The Interaction with Cosmetics and PerfumesCosmetics, sunscreens, and perfumes contain complex organic and petroleum-based compounds (oils, fragrances, alcohols, etc.). * Depleted Chlorine: Like body oils, these substances are organic contaminants that the chlorine must work to break down. They consume the free chlorine, reducing its ability to kill germs.

* Scum and Clogging:

Many cosmetic oils are water-repellent. They can form a scum line around the hot tub and, worse, clog the pores of your filter cartridges, making the filtration system less effective. * Other Byproducts: Chlorine’s reaction with these complex organic molecules can form a wide array of other Disinfection Byproducts (DBPs), such as Trihalomethanes (THMs). While many of these are at low concentrations, they are also contaminants that need to be removed from the water.How to Fix ThisThe common practice to deal with the buildup of chloramines, oils, and cosmetics is shocking the hot tub: * Shocking (Oxidation): This involves adding a high dose of an oxidizer (usually a non-chlorine shock, or a very high dose of chlorine) to the water. The purpose is to break the chemical bonds of the chloramines and other organic waste, essentially “burning them off” so they can escape as gas or be filtered out. This regenerates the Free Chlorine and restores the water’s sanitizing power.Do you have any questions about

Shocking interval’s

How often you should shock a hot tub to manage these contaminants?

That’s a crucial question because the frequency of shocking directly impacts your water quality, comfort, and the lifespan of your equipment.The general recommendation for hot tub shock frequency is at least once a week for maintenance, but it heavily depends on your usage.Here is a guide based on typical usage levels and the different types of shock:

📅 Hot Tub Shocking Schedule| Usage Level |

Recommended Frequency | Primary Goal ||—|—|—|| Light Use (1–2 soaks/week) | Every 10–14 days | Regular maintenance and oxidation. || Moderate Use (3–4 soaks/week) | Weekly | Standard schedule to destroy built-up chloramines and oils. || Heavy Use (Daily use or parties) | After each heavy use | Immediately break down the large load of sweat, oils, and cosmetics introduced by multiple bathers. || As Needed (Any usage level) | When the water looks cloudy or has a strong chemical smell (chloramines).

| Emergency oxidation to restore water clarity and safety.

|💡 Which Type of Shock to Use?There are two main types of shock, and they serve different purposes:1. Non-Chlorine Shock (MPS – Potassium Peroxymonosulfate) * Primary Use: Regular Maintenance and Oxidation. This is the preferred weekly shock for most users. * What it does: It is a powerful oxidizer that breaks down organic waste (oils, sweat, chloramines) and reactivates your primary sanitizer (chlorine or bromine) so it can get back to killing bacteria. * Benefits: It does not significantly raise your chlorine level, meaning you can usually re-enter the hot tub after 15–30 minutes. * Best Time to Use: Weekly, or after every use if you want a simple way to keep the water fresh and clear.2. Chlorine Shock (Dichlor) * Primary Use: Deep Cleaning and Sanitizing. Use this for more aggressive treatment. * What it does: It acts as both a potent oxidizer and a high-dose sanitizer. It’s used to reach “breakpoint chlorination” to kill bacteria, algae, and fully burn off heavy chloramine buildup. * Benefits: Highly effective at eliminating severe contamination issues (e.g., green or cloudy water). * Wait Time: You must wait until the Free Chlorine level drops back down to a safe range (typically 1–3 ppm), which can take several hours, and sometimes up to 24 hours. * Best Time to Use: After draining and refilling the tub, or after a party with heavy bather load.Key Indicator: Test Strips are Your GuideThe most accurate way to know when to shock is to check your water chemistry using test strips: * Shock when: Your Total Chlorine (TC) is higher than your Free Chlorine (FC). This means you have a buildup of Combined Chlorine (Chloramines), and it’s time to “shock” the water to break them down.Do you currently use a chlorine or bromine system in your hot tub? Knowing this can help fine-tune your specific shocking routine.

Editors Note:

This information is for consumers,and may generate questions to be addressed by the manufacturer’s instructions of hot tubs. Please rely on their authority, but we would like to hear from your you on your experience in our comments.