There are about as many “correct” ways to keep fish thriving in an aquarium as there are aquarium keepers. It is not an exact demarcation. And Mother Nature is extremely flexible.
But the aquarium options can be divided into six very broad options. Here are three “fish-only” aquarium options:
| Fish-only parameter | Lghtly stocked | Breeder | Heavily stocked |
|---|---|---|---|
| Fish stocking | Light | Light | Heavy |
| Plants | None | None to moderate | None |
| Typical substrate | Sand or gravel | Bare bottom | Sand or gravel |
| Aeration | Moderate | Heavy | Heavy |
| Lighting | Any | Any | Any |
| Typical water changes | 25% every month | 25% every other week | 50% every other week |
| Biofiltration | Light | Moderate | Very Heavy |
| Degree of difficulty | Easy | Moderate | Moderate |
And here are three planted aquarium options:
| Parameter | “low-tech” or “Walstad”planted | “high-tech” planted | Many fish, many plants |
|---|---|---|---|
| Fish stocking | Light | Very Light | Moderate |
| Plants | Heavy | Heavy | Moderate |
| Typical substrate | Garden soil with cap | Commercial fused product | Various |
| Aeration | Light | Light | Heavy |
| Lighting | Moderate 4 on 4 off | High | High |
| CO² | No | Yes | Yes |
| Fertilization | No | Yes | Heavy |
| Typical water changes | 50% every four month | Never | 25% every other week |
| Biofiltration | Light | Light | Heavy |
| Degree of difficulty | Moderate | Difficult | Very Difficult |
All six of these types of aquariums are “correct” and have an infinite number of variations.
Tolerance is in very short supply in today’s world. This intolerance extends to keeping aquariums. If you read the forums and groups on the internet there is a constant barrage of “no, you can’t” rather than “you will have challenges but have at it”. An aquarium is a natural system and Mother Nature is extremely flexible. So if you have an idea for an aquarium, go for it!
Now I will go ahead and do exactly what I hate, namely try to caution one against one type of aquarium. Unfortunately, many newcomers to the hobby buy both a moderate amount of decent sized fish and a moderate amount of plants to start their hobby. This is one of the most difficult aquariums to keep. Generally, the plants die and in rare cases, the fish die, and the newcomer gives up the hobby. Newcomers should skip the plants and start with a lightly stocked “fish only” aquarium with several small fish and plastic plants till they get to understand the hobby better. But if you like a challenge go ahead and try it.
If one wants plants with their fish some plants are the exception and simply can’t be killed and which seem to live under any conditions. While they will get some algae on their leaves the leaves are resistant to being smothered by algae. And they seem to live in all substrates under all conditions with no fertilizer at all. They even live in very low light conditions.
The plants that seem to fit this description are Anubias (just don’t put the bulbs INTO the substrate), Amazon Sword (Echinodorus amazonicus), Java Fern (Leptochilus pteropus, synonym Microsorum pteropus), and Java Moss (Taxiphyllum barbieri). Java fern and Java moss are both “epiphytes” and need to be either attached to a surface like a piece of wood or they need a very open substrate like aquarium gravel. If you bury the crown on Java fern in sand it will die.
In the aquarium below note a large number of fish and a large number of plants. Also, note the cloudiness of the water and the scum on the water’s surface. I would predict these fish and these plants will not live long. But I could well be completely wrong!
To see photos of many types of Aquariums one can load the following link (note the file is large and takes a long time to load)
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