---
url: https://www.eurocovers.eu/vs/uv-treatment
title: Floating cover vs. UV treatment for algae — comparison
description: Floating covers prevent algae by blocking light; UV treatment kills algae downstream. Comparison on cost, scope, and integration with reservoir operations.
updated: 2026-05-25
---

# Floating cover vs. UV treatment for algae — comparison

> Floating covers prevent algae at the source by blocking light (95%+ suppression, no power, no operating cost); UV treatment kills algae and pathogens downstream of the reservoir at point-of-use, with continuous power and lamp replacement costs.

For potable water utilities, floating covers and UV treatment are complements, not alternatives.
Covers prevent algae from forming in storage; UV disinfects at point-of-use. Most modern designs
deploy both.

## What each does

**Floating covers** stop algae at the storage reservoir by blocking the sunlight that drives
photosynthesis. They also reduce evaporation and odor. No power, 25-year lifecycle.

**UV treatment** uses ultraviolet light at the point of distribution to kill microorganisms
(including residual algae and pathogens) that have already formed. It does not prevent formation;
it disinfects.

## Complementary design

- **Cover the storage reservoir** → algae load on the UV system falls 95%+.
- **UV disinfection at distribution** → handles the residual + meets disinfection compliance.

The combined design reduces UV operating cost (lamp life, energy, cleaning frequency) because the
algae load is much lower at the UV inlet.