15. Planted Aquarium – Aquarium Science

Types of Planted Aquariums

There are as many types of planted aquariums as there are hobbyists with planted aquariums. Each tank is different. But there are six broad categories of tanks. Three are “Natural” systems with no chemical fertilization or carbon dioxide gas (CO₂ gas injection) to speak of.

	Low tech	Walstad	Father fish
Plants	Only very easy	Only easy ones	Only easy ones
Fertilizer	Fish waste	Fish food in excess	Fish waste
Bottom substrate	Typically sand	One inch nitrogen poor organic soil	Three inch sand
Capping substrate	None	One half inch gravel	Three inch sand
Carbon dioxide	None	From Soil and Food	From Soil and Food
Lights	Moderate 16-8	Moderate 5-4-5-10	High 14-10
Filter	Small	Small	None
Aeration	Airstones	None	Some
Water movement	Some	Very light	Some
Number of fish	Light	Light	Heavy
Inoculate	None	Soil	Pond mud
Difficulty	Easy	Easy	Moderately

Then there are those systems which use chemical fertilization and/or carbon dioxide gas injection:

	Hau method	Hybrid	High Tech
Plants	Any	Any	Any
Fertilizer	Only fish food and root tabs	Light fertilization	Heavy fertilization
Bottom substrate	3 inches of gravel	1 inch wood pellets	2 inch commercial planted aquarium soil
Capping substrate	None	1 inch coarse sand	None
Carbon dioxide	Low tech bottles	From the pellets	Heavy injection
Lights	Light 8 on – 16 off	Moderate 4-4-4-4-4-5	Very High 14 on-10 off
Filter	Small	Big	Varies
Aeration	Little	None	Varies
Water movement	Little	Some low in the tank	Varies
Number of fish	Moderate	Light	Light
Inoculate	Plants	Pond mud	None
Difficulty	Easy	Moderately	Moderately

Recommendations

It is POSSIBLE to have a successful planted aquariums which is a very simple affair without carbon dioxide additions and pretty much ANY combination of substrates, plants, aeration and filtration. I have only noticed one “guideline” with planted aquariums that is VERY challenging to break. This one “guideline” is:

Only have a Few Small Fish in the Planted Aquarium

Any experienced aquarium owner will tell you that when you enter the hobby there is a decision you must make. Do you want an aquarium of all fish or do you want an aquarium of largely plants? Do you want a fish aquarium or a planted aquarium? Creating a well planted aquarium with a heavy loading of fish is extremely difficult. Even a moderate amount of fish with a lot of plants is challenging. But then many enjoy a challenge.

In our meanderings over the years we have found several ways to have decent numbers of decent sized fish in an aquarium. Mother Nature is VERY flexible. These methods are reviewed in this link:

15.11. Many Fish Many Plants

If one really wants plants with their fish there are some plants which are the exception and simply can’t be killed and which seem to live under any and all 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 under all conditions with no fertilizer at all. They even live with very low light conditions.

These plants include 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.

Heavily planted aquarium with a few fish

Definition of a “Planted Aquarium”

There is a distinct difference between a “planted aquarium” and an “aquarium with plants”. Beginners seem to think that one can put a few plants into an aquarium and within months the plants will multiply and take over the aquarium. It doesn’t work that way.

The aquarium below is one such aquarium. Note that the aluminum plant in the middle is terrestrial and will die in water. The other five species of plants will probably fare little better as there is an air stone operated sponge filter in the back. Air stones insure that the CO₂ level is too low for most plants to survive.

For an example of how not to set up a planted aquarium, let’s use a sixty-gallon beginner’s “aquarium with plants”. Let us add six different species of plants into a sixty gallon aquarium at a density of one plant per ten gallons, six plants in the sixty gallon. This is what one would term “an aquarium with plants”. Of the six plants in our example, two die back in the first month to stubs, two do nothing and two begin growing slowly.

The beginner is adding the recommended dose of a complete fertilizer twice a week, just like the directions say. They leave the light on from 7 in the morning till ten at night (15 hours). Because they are way over fertilized the two stubs and the two plants doing nothing die completely.

And the two plants remaining struggle because they are getting the fertilizer loading for about fifty plants and algae are thriving in the high light condition. Finally all the plants die, algae takes over the aquarium and the hobbyist is puzzled as to what happened. After all, “I fertilized per the directions“.

Experienced hobbyists who put together the beautiful high tech planted aquariums which are wall to wall with plants all either raise or buy plants in large quantities. They would plant this sixty-gallon (237 liter) aquarium with TEN plants of each species, sixty plants total. They would slowly ramp up the fertilizer along with the lighting over the span of a few months. They would NOT add any aeration. They would add some sort of CO₂ (including soil substrate) to bring the CO₂ level from 3 ppm to at least 10 ppm. This is a “planted aquarium”.

If one only has a limited budget and cannot buy sixty plants at once (at $5 per plant that is $300) one can raise the plants. But note that takes some thought. Here is a link on how to do it:

15.12. Propagating Plants

Recommendations for Planted Aquarium

There are several very general, frequently not followed, recommendations for a planted aquarium:

Light stocking of fish smaller than two inches (5 cm)
A carbon dioxide (“CO₂”) level above 10 ppm first thing in the morning
A plant every three inches (7,5 cm) across both the length and the width of the aquarium
Little surface movement of the water and no air stones
Slowly ramp up light and CO₂ over a span of months.

Note that fertilization is NOT included in this list. Fertilization is MUCH less important than many seem to think.