What Causes Green Fish Tank Water & How to Fix It 

If your aquarium has suddenly turned into a murky green soup, you’re not alone. Green water is one of the most common (and most frustrating) problems hobbyists face. You clean it… it comes back. You change the water… it comes back. You try additives… it STILL comes back.

Why?
Because most people never fix the actual cause.

In the video below, DALUA Fishroom breaks down the two real reasons green water keeps returning — and the five simple steps to eliminate it permanently. Once you understand the root cause, you’ll finally be able to enjoy crystal‑clear water again.

The 5‑Step Fix

Here’s the core method explained in the video:

1. Reduce Light Exposure

Cut back on direct sunlight and shorten your aquarium light cycle.

2. Control Nutrients

Overfeeding and decaying waste fuel algae growth. Feed less and clean more.

3. Improve Filtration

A strong biological filter helps starve algae of what it needs.

4. Increase Water Changes

Frequent, smaller water changes help reset nutrient levels.

5. Add Live Plants

Plants outcompete algae for nutrients, restoring balance naturally.

Follow these steps consistently and you’ll see your water clear up — and stay clear.