---
title: "Ponds and lakes: problems we treat | Alchemal"
url: "https://alchemal.com/ponds-lakes/problems/"
description: "The problems we treat in ponds, lakes, and lagoons, what is actually happening in the water, and what usually fixes it."
source: "Alchemal — alchemal.com"
---
# What goes wrong in ponds, lakes, and lagoons

Each page explains what is actually happening in the water, what usually fixes it, and when oxygenation is not the right tool.

10 problems

## What are you seeing?

- [Pond algae: fix the conditions that favor it Green water, string algae, mats that return on schedule. See what favors the bloom and what changes it.](https://alchemal.com/problems/pond-algae/)
- [Murky pond water: find the cause, then clear it Brown, cloudy, or hazy water can have several causes. The fix depends entirely on which one you have.](https://alchemal.com/problems/murky-pond-water/)
- [Pond muck: digest the organic layer Years of sludge on the bottom and dredging feels like the only option. See what oxygen can digest, what it can't, and how we measure it.](https://alchemal.com/problems/pond-muck/)
- [Blue-green algae: safety first, then restoration Suspect a toxic bloom? Keep people and pets out and get it tested. Safety steps come first; the restoration conversation comes later.](https://alchemal.com/problems/toxic-algae-blooms/)
- [Aquatic weeds: what oxygen can and can't do Weeds taking over, or is it algae? The fix is different for each, and telling them apart comes first.](https://alchemal.com/problems/aquatic-weeds/)
- [Stagnant water and mosquitoes: what actually works Still water and a mosquito season that won't quit. Here is the ecology behind it, and which tools act now.](https://alchemal.com/problems/stagnant-water-mosquitoes/)

## What are you smelling?

- [Pond odor: the smell is your pond out of oxygen Rotten eggs or sewage at the water's edge. See what makes the smell, why surface fixes never hold, and what stops it.](https://alchemal.com/problems/pond-odor/)
- [Lagoon odor and sludge: keep the column aerobic Odor complaints, crusting, and sludge that makes pumping harder. One anaerobic cause sits behind all three.](https://alchemal.com/problems/lagoon-odor-sludge/)

## What are you losing?

- [Fish kills: the overnight oxygen crash, prevented Fish gasping at the surface, a loss overnight. See what causes the oxygen crash and how a continuous reserve prevents the next one.](https://alchemal.com/problems/fish-kills-low-oxygen/)

## Tired of treating it?

- [Tired of algaecide every month? Exit the treadmill You've done the math on the jugs already. See why the monthly cycle escalates and what it costs to step off it.](https://alchemal.com/problems/tired-of-pond-chemicals/)

## Tell us what your water is doing.

A specialist reads your description and replies in writing: what it usually means and what we would measure first.

[Get a free assessment](https://alchemal.com/assessment/)