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Green saltwater pool water: How to fix it? Causes and solutions, along with a review of using Algae stop CU to make it crystal clear again.

Last updated: 2 Dec 2025
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# Green Algae Problems in Saltwater Pools

## What causes it? How to fix it permanently? (Easy Guide for Pool Maintenance)

Many saltwater pool owners frequently encounter **Green Water / Algae blooms**, even when the salt chlorinator is running constantly.
In reality, a **Salt Pool is simply a type of Chlorine Pool**. If the water balance is not appropriate, algae can grow just as easily.


# Major Causes of Green Algae in Saltwater Pools

## 1) Insufficient Chlorine

* The salt chlorinator is not running for enough hours.
* The Output percentage is set too low.
* High bather load / Rain / Strong sunlight causes chlorine to deplete quickly.
When chlorine drops below **1 ppm**, algae will start to grow immediately.

## 2) pH Level is Too High

If pH > 7.8, chlorine cannot function effectively, even if the ppm reading seems sufficient.
The result is: **"Chlorine is present, but it cannot kill bacteria."**

## 3) Poor Water Circulation

* Pump running time is too short.
* Inlet nozzles are not distributing water throughout the pool.
* There are "Dead Spots" behind ladders/pool corners.
These are the spots where algae starts to grow easiest.

## 4) Dirty Filter / Not Backwashing

Clogged sand filter/media
= Cannot trap dirt effectively
= Becomes **"Food"** for algae.

## 5) Dust, Leaves, and Organic Debris

Homes with trees near the pool often face this issue. Algae grows very fast, especially during the rainy season and strong sunlight.

---

# Before Fixing: Check 4 Important Things

Pool caretakers should follow this order before adding any chemicals.

### 1) Check pH

It should be between **7.2 - 7.6**

### 2) Check Chlorine

Must be at least **1-3 ppm**.
If chlorine is zero, it is recommended to **Shock Chlorine** or increase the chlorinator's running time.

### 3) Clean Filter (Backwash)

Because dead algae will flow into and clog the filter significantly.

### 4) Scrub Floor and Walls

To allow chemicals to reach the algae fully, preventing it from hiding under a biofilm.

---

# How to Fix Green Algae in Salt Pools (Step-by-Step)

### **Step 1: Balance the Water**

* pH: 7.2 - 7.6
* Chlorine: 1 - 3 ppm
* Turn on the circulation pump for at least 12 hours.

### **Step 2: Scrub Algae Thoroughly**

Scrub walls, floors, dead spots, and ladders.
Algae floating in the water is a good sign.

### **Step 3: Add Algaecide**

To kill floating algae and prevent further growth.

### **Step 4: Run Filter System 12-24 Hours**

The water will start changing from Green -> Light Green -> Cloudy -> Clear.

### **Step 5: Backwash + Vacuum**

Remove all dead algae from the system.

---

# Preventing Algae Recurrence

### Check Chlorine + pH 1-2 times/week

### Backwash at least once a week

### Run pump suitable for pool size (Generally 8-12 hours/day)

### Collect leaves and debris daily

And importantly:
**Use a preventative Algaecide (Maintenance Dose)** to inhibit new algae growth, especially during rainy seasons and summer when algae grows fastest.


# Recommended Product: Algae stop CU

After fixing the system, choosing the right algaecide is crucial. **Algae stop CU** is a popular choice for salt pools because:

### Kills Algae Fast

Copper destroys algae cell walls directly. Fast acting, water clears up quickly.

### Ideal for Salt Pools

Enhances chlorine efficiency, especially when the salt chlorinator cannot keep up with demand.

### Easy to Use

Pour around the pool edge while the pump is running. Disperses quickly, requires small dosage.

### Can be used for both Curing and Prevention

* **Kill dose:** When algae is present.
* **Maintenance dose:** Every 1-2 weeks.

### Safe when used according to label

Does not stain pool walls, does not discolor water.


**Salt pools are the easiest to maintain, but water balance must be correct.**
When green algae problems occur: Adjusting pH, Increasing Chlorine, Scrubbing, and Running the System are the core solutions.
And to prevent the problem from returning,
**Supplementing with Algae stop CU helps control algae for the long term. Suitable for home pools and all service jobs.**

Order Algae stop CU

Tags :
AlgaeTreatment
SwimmingPool
GreenPool
PoolAlgae
AlgaeProblem
PoolChemicals
AlgaeStopCU
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