Low Maintenance Planted Aquarium

Background:

I have always found that nature tends to take care of itself if provided the right materials. I think this is doubly so when you have an ecosystem that is able to run by itself.

The idea of a self-sustained aquatic system, where the waste of one organism is broken down and used as food for the other organisms which provide nutrients and food for other organisms in a constant ever-looping cycle has always fascinated me. I have tried to replicate this idea of a closed loop ecosystem as much as possible in my aquariums.

The main parts of this aquatic system are:

The soil and microorganisms in the soil:

This part breaks down nitrites and nitrates from larger organism waste and provide nutrients and a rooting system for the plants (a small Winogradsky column will form in a natural aquatic soil setting)

The plants:

This part provides a filtering system for the water and removes CO2 buildup in the water while providing oxygen to the larger organisms. depending on additional equipment, such as a CO2 tank, these large plants can also deter growth of algae on the aquarium glass and environment.

The macro-organisms:

This part can vary quite largely, but the main idea to keep in mind here is Bio-load. Bio-load refers to the amount of waste buildup that needs to be broken down and repurposed as nutrients for other parts of the ecosystem. A general rule of thumb is that a higher Bio-load leads to more effort to keep an ecosystem in check. Likewise, larger organisms have larger Bio-loads.

Macro-organisms can be as small and versatile as freshwater shrimp or crawdads (LOW Bio-load) or bigger organisms such as small fish or small frogs (MEDIUM Bio-load), or bigger Bio-loads, such as predatory fish (HIGH Bio-load).

Additionally, the more macro-organisms that are in the system, the larger the Bio-load.

Light:

this is not normal aquarium light, but actual sunlight (for small amounts throughout the day, or artificial grow lights that can replicate the requirements needed for plants to grow indoors.

10 gallon aquarium tank:

The shallower the better, but deep systems can also work as well.

small, cheap, cascade filter (this mainly for movement of water and to agitate the surface, if the Bio-load is only shrimps and small frogs, a small pump to circulate the water in the tank will work perfectly fine).

(mainly for water flow and exchange of nutrients in the water to the plants and soil)

aquatic plants:

(Petco and Petsmart normally has it, I have had better luck finding healthy plants at local aquarium shops) these can be floating, submersive or emerging plants. the more air the plants can acquire, the more air they can return back into the aquatic system.

Aquarium grow light:

I have found that one light is good for 10 gallons and up to 30 gallons. It is possible to give the plants too much light.

https://www.amazon.com/NICREW-ClassicLED-Aquarium-...

Old soil that has not been fertilized or treated for at least a year:

(IMPORTANT: you do not want treated or fertilized soil, the excess nutrients can AT BEST create a huge Biological or Chemical Oxygen Demand (B.O.D. or C.O.D.) in the system which results in rapid growth of algae or micro-organisms which then leads to a rapid death of such organisms as they deplete the more finite resources of the system. AT WORST, create an inhospitable environment for any plants or macro-organisms to live in and you will have to throw out and clean out the system and start over)

Shrimp:

ghost shrimp, amano shrimp, cherry shrimp or other colored shrimp

OPTIONAL: larger organisms such as fish or frogs

(NOTE: the bigger the organism, the more work and cleaning that is needed for the system. shrimp and plants require almost zero effort to maintain apart from adding more water every now and then)

like with all tanks that hold living organisms, and especially aquatic organisms, don't use crazy chemicals to clean it right before you add anything to the tank. If needed, you can use a diluted bleach solution to make sure the tank is free from debris and previous microorganisms, just be sure to follow up with a food grade acid rinse (Star-San for the homebrewers, food vinegar for anyone else) followed by heavy rinsing and a 24 hour soak of filtered/ non-chlorinated water. The longer the soak, the better. I find 24 - 48 hours to be plenty.

the amount of soil at the bottom is important. Too little, and there are not enough microorganisms and not enough depth of soil to create the complex system of breaking down nitrites and nitrates to more easily consumable nutrients for the plants.

Too much soil will create pockets of dead zones in the soil where the nutrients either cannot reach the desired micro-organisms or cannot escape to the next level of microorganisms.

If you have ever seen a Winogradsky Column, you will understand that micro-organisms at different depths will congregate at certain levels to acquire the best and most amount of nutrients possible, and that the waste of one microorganism is the nutrients of another.

a good rule of thumb is about 1 - 1.25 inch of soil at the base of the aquarium, this provides enough soil for a small column to form while still allowing the waste of the macro-organisms to penetrate a good portion of the soil to keep a high efficiency of waste recycling.

NOTE: if you wanted to create a sloped effect in the aquarium, where one side of the plants or habitat is higher than the other, add the rocks or sand FIRST before adding the soil. The soil MUST (for best effects) be 1 - 1.25 inches deep and level from the bottom of the water as possible.

Once this is done, use any aquarium gravel, (not sand) to keep the soil in place, 3/4 - 1 inch is best to layer on top of the soil, try to be as level as possible.

add enough water to cover the soil and gravel, be careful that the water does not directly hit the gravel to make sure it does not disturb the gravel/soil bottom. Using a gallon water bottle with a shallow tupperware at the bottom and pouring slowly is a good way to minimize the risk of this happening.

Once this is done, you will want to add the plants.

if the plants are rooted: be sure to push the roots down to the soil level as gently and firmly as possible, using the gravel around to cover any exposed soil. soil will occasionally pop up into the main water system during this process, that is perfectly fine, it will fall as sediment within a few hours.

NOTE: be careful in adding the water, a deeper level tupperware works well as long as you pour careful;y into the tupperware and make sure it doesn't have too strong of a back flow after leaving the tupperware container. the more water that is in the system/aquarium, the easier it is to add more water without disturbing the delicate bottom layers and plants.

Add the aquarium light and let the system rest for at least 24 hours (longer is better, especially for expensive organisms) before adding any macro-organisms to the system. If there is a problem in the soil, you will see it in the plants and there does not have to be any unnecessary deaths of shrimp or fish because of it. Plants are a lot cheaper and a lot more tolerant of chemical and C.O.D./B.O.D. demands than macro-organisms.

A note on timers for aquarium lights: if you are using a timer, I would recommend a 12 hour light cycle with the light turned off in the middle of the day for 2 hours, or a 14 hour light cycle with the light turned off for 4 hours. This gives the plants a rest time from the artificial light and allows for some CO2 to build back in the system before the light turns on again. Photosynthesis can deplete the CO2 in the system within about 8-10 hours leaving less CO2 for photosynthesis in the afternoon and allowing for algae growth to gain an advantage over the plants. I have seen other people use a 5 hour on, 4 hour off, 5 hour on cycle as well that also works very well.

The graph above shows that CO2 levels in the system can vary depending on your light cycles.

Emerging plants and floating plants: If there is a strong cover of plants on the surface, the light should stay on continuously for 10-12 hours.

A note on natural light from the sun: It is best for the aquarium to get bright INDIRECT sunlight for 6-9 hours a day. of there is not enough sunlight, the plants will start to lose their chlorophyll color and will get paler and paler.

Direct sunlight will cause rapid growth of algae, so you will have to clean your tank more often, try to avoid direct sunlight as much as possible.

Shrimp and crawdad are a great way to make sure the aquarium stays clean with the most minimum Bio-load. They also can look very pretty too. Fish are bigger and can always be added, but if the Bio-load is too large, you will see effects in the system (build up of waste/sediment at the bottom of tank or discoloring of plants in the system). very bad effects will show up as macro-organisms trying to breathe at the top the system for cleaner/purer air.

A good system will take care of itself, if you wanted to go farther, you can create a replica biotope of a certain area. Freshwater systems are a lot easier to maintain than saltwater systems (salt water systems require a HUGE amount of space and light to be self-sufficient, think of the size of oceans and how they are compared to ponds or lakes). Overall, any biotope can be replicated, if you are willing to spend more time, money, and effort into the system.