The Discus Learning Center (DLC)

The Discus Learning Center is a collection of articles, forming a comprehensive knowledge base for mastering all aspects of the art of keeping and collecting discus fish. It is a completely free resource dedicated to discus and the discus community.

Begin by browsing the articles below. Each article has a comment section on the bottom so that you may engage our experts -- and each other. Let's get started on our journey into the wonderful world of the incredible discus fish, and learn why the discus fish lives up to its nickname, the "King of the Aquarium."

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Everything you Ever Wanted to Know about Filters, but were never Told, By Jim E. Quarles
Before we get into the different kinds of filters we should clearly understand the purpose of any filtering system. Basically a filter does one of three things. 1. It removes solids from the water. 2. It provides a surface area for bacterial growth needed to change chemical compounds from one to... Read More
CO2 in a Discus Aquarium
CO2 is the scientific formula for carbon dioxide and occurs due to a reaction between the elements carbon (C) and oxygen (O) . Carbon and oxygen are 2 of the most important building stones of life for any organism.   What is the relationship between tanks and CO2? To keep it simple it’s... Read More
Plans for a Custom Built Wet/Dry Filter
Here's the base for the wet/dry filter.  It's really just an aquarium (36"x10"x18") with some glass panels siliconed inside to allow water to flow through the media. Right click on the image below and select "open in a new tab."   Now I've put the guideline strips of acrylic into... Read More
Continuous Drip Water Changes
I use a continuous drip system to perform water changes on my growout tanks.  It's a very cheap & simple system to install.  It can get complicated depending on what you're trying to accomplish.  I'll show my system with some suggestions to simplify it.  I bought the... Read More
Drain & Fill Water Changing Method
I currently use the Drain & Fill method to change all water in my tanks.  I prefer it because it wastes the least amount of water and doesn't require drilling tanks or building/buying overflow boxes.  There are many ways to drain & fill a tank, it ain't Rocket Science.... Read More
Different Types of Water Changing Strategies
Nothing gets talked about in the Discus world more than changing water.  There are more opinions on the frequency & size of water changes than most aspects of Discus keeping.  There are also many ways to do this task.  I'm going to outline the methods that I have tried and try... Read More
Reverse Osmosis and Discus Fish
This article will explain the reverse osmosis water filtration process and how it is used in soft water species aquariums, including angel fish and discus fish. RO water is also used to build water for marine and reef aquariums. A reverse osmosis filter is not used to filter water that is inside... Read More
Beginner FAQ: Partial Water Changes
Purpose of Water Changes   The solution to pollution is dilution; water changes replace a portion of ``dirty'' water with an equal portion of clean water, effectively diluting the concentrations of undesirable substances in your tank. In an established tank, nitrate is the primary toxin... Read More
Municipal Tap Water in the Aquarium
Most people use tap water in their tanks; it is cheap and easy to use. Unfortunately (for aquarists), local water companies add chemicals to the water to make it safe to drink (e.g., chlorine or chloramine to kill bacteria). More recently, concern about water flowing through older lead pipes has... Read More
Regeneration of Reverse-Osmosis (RO) Water
Reverse-Osmosis (RO) water will not sustain the life of a discus fish in its pure form. Following are three methods of regenerating RO water for the desired hardness and stability of PH.   Mixing dechlorinated tap water with RO water This is the most popular and easiest method of... Read More
Cloudy Aquarium Water
Cloudy Aquarium Water   The issue of cloudy water can be a baffling phenomenon for many aquarium owners. Unfortunately, there is no single answer as to why your aquarium water is cloudy because there is no single cause. However, based on the color and circumstances under which cloudy... Read More
How to Clean Aquarium Substrates
Aquarium substrates form a critical part of your fish tank. It serves not only as a decoration, but also as a filter. Because of this, it tends to harbor a lot of debris and waste. Cleaning gravel involves the process of removing some aquarium water. Because of this, most aquarium hobbyists will... Read More
Frequency of Discus Water Changes
Introduction   Clean water is a key to discus fish health. A clean tank with a constant exchange of new, fresh water will work wonders for your discus’ health. In this article, we will explain how to keep your water clean without requiring fancy equipment like reverse osmosis filters... Read More
Best Aquarium Water Test Kits
Testing aquarium water is a key component of maintaining a healthy environment for fish. Below are a list of aquarium water test kits and some information about them.   Best Aquarium Water Test Kits – Master Test Kits Combination, or Master, test kits are touted as the perfect way to... Read More
Water Parameters for a Discus Aquarium
If you do a Google search for Discus water parameters you will see a lot of conflicting information. Many Discus owners become obsessed with water parameters to a point where they take the fun out of the hobby. We as Discus owners ARE NOT chemists! So- don’t worry too much about the water... Read More
Best Filters For Discus Fish
Filtration is very crucial and its importance cannot be brushed off in any fish tank or aquarium. The fact of the matter is that the higher the level filtration in the fish tank the better it is for the fish. Discus fish require one of the highest levels filtration because of their messy nature.... Read More