Natural Planted tank:
Soil based with lots and lots of stem and floating plants. Common snails and shrimp complete the little ecosystem-everything has a job.
Plants functions as the filtration-All livestock and anything organic function as the ferts-When the organics start to break down and decomp-they naturally produce CO2 that the plants need. Shrimp also shred dead/dieing organics/plant matter so that it will break down faster and eat some algae. Snails-eat organics and dead/dieing plant matter and some algae.
Soil based tanks are as close to a complete ecosystem you can create in a closed system/aquarium. Everything works together to create the Balance.
It can take about 3 months for a soil based tank to mature. Once the soil has started its life under water, is alive and full of critters/microorganisms. I like to remove my filter or water movement in my 10gal and under tanks. I do use water movement in my 20gal and larger.
-in properly setup soil based tank with lots of plants you don't need to worry about the nitrogen cycle or do anything special-It happens on its own. The silent cycle.
Often with heavy planted tanks-it will take a long time if ever to see the nitrate reading we normally look for that tells us cycling stage/completeness-But the nitrogen cycle is happening-its silent.
If you properly setup the soil based tank-you can safely add all your livestock on the same day you set it up.
Once mature-water changes are limited and this can vary from once a month to 4-5 times a year. If you want that really clean tank floor with an organized look-the soil based may not be for you.
Over cleaning-water changes and vacuum can upset the balance, however, your water should always look crystal clear-this tells you that you have good balance and the plants, microorganism, shrimp, snails and fish are doing their job.
-Look for organic type potting soil, top soil or use dirt from your yard. You don't want any added ferts, chemicals...etc.....
Sift the soil or pick through it to remove any large pieces of organics and wood.
In 1-10gal tanks use 1-1.5 inches of dirt
In 20-55gal tanks use-1.5-2 inches of dirt
In over 55gal-use 2-3 inches of dirt
-use either-pool filter sand, play sand or small diameter gravel.
The cap is to help hold the soil in place and you only want to use half as much cap as you do soil.
-If using large based items-like big rocks or driftwood-along with more than 1 inch of dirt. Place the hard scape item on top of the first 1 inch of dirt-then add the rest of the dirt and cap.
Place the filter and heater in the tank before you place hard scape items. This will help you with proper placement and then place the hood if you are using one to check that everything will fit properly-You want the overflow of the filter to be directed over a hard scape item so it doesn't cause a kick up. Check the intake to insure that it isn't too low to the dirt/cap line-you may need to shorten the intake or place a flat rock under it so it doesn't suck up the soil/cap and ruin the filter.
-proper lighting is really important-without the proper color temp bulb the plants can't see the light to use it for photosynthesis. Without good plant growth the soil based tank will crash.
You want-"Daylight" 6500k bulbs-watts will vary based on length of bulb
You want to change both the bulb and the starter every 12 months
-even if they still work since florescent bulb intensity can be lost over time.
The partition between the light and plants
-need to either be removed all together or ensure it is kept clean for best light penetration to plants.
-keep the lights on 10-12 hours. Plants naturally are on 10h/day PP with 1 hour before and after of less intense light.
Too short a PP or wrong color temp bulb, old bulbs can trick the plants into thinking its a season change and time to go dormant, die or flower.
Poor plant growth can result in poor water quality. You should need to make your first plant trim in 7-10 days after planting.
Its normal, expected and a sign of a healthy system, however, since this is a closed system-even the good algae needs to be manually removed on occasion. With soil based systems that have proper balance you shouldn't have algae issue-you will have some-but as long as you have enough of the right species of thriving plants-they should out compete problem algae.
If you can't start a soil based tank with enough of the right species of plants-DON'T set one up...It is important to have enough of the right species of plants on hand, correct lights from the start-otherwise the system might crash.
You want to start with lots of fast growing stem plants and some floating plants. You can add the moss, ferns, anubias to your hard scape items and add some rosette plants too.
Plants I like to use:
Najas indica (naja grass)
C. piauhyensis (red)
Hygrophila dfformis (westeria)
H. corymbosa (giant hygro)
H, siamensis (thin leaf)
Vallisneria americana-var Biwanesis
Echinodorus bleheri (amazon sword)
E. tenellus (chain sword)
Nymphaes stellata (red lily)
Microsorium pteropus (java fern)
Vesicularia dubyana (java moss)
Pistia stratiotes (water lettuce)
Limnobium laevigatum (frogbit)
Lemna minor (duckweed)
Once the hard scape items and fully planted-make water only changes until the water is clear-Turn on the filter and heater-Once at temp-add the livestock after proper acclimation.
If you don't have trumpet snails that burrow to add-be sure and poke the soil a couple of times a week with either chopstick, wooden spoon...etc.....This will help prevent anaerobic soil. Once you make your first trim, plants are thriving-the roots of the stem plants will help prevent anaerobic soil by pulling oxygen into the soil layer.
You will need to make 1-3 times a week 25-50% water only changes for the first 1-2 weeks-Then decrease as you see plants growing/thriving to 1-2 25-50% a week. By the 3 month stage and provided plants are thriving and you have had to make at least 4-5 trims on the stem plants-Reduce water changes to monthly 50% and remove the filter if you want. As the tank matures-plants thriving you can use your judgment on water changes and reduce them further.
I don't use any added ferts or inject CO2-neither are needed in soil based balanced systems-They make everything they need if allowed, however, adding an extra pinch of fish food weekly is a great plant food for NPT's.
Once you have 1 thriving soil based tank-you will soon need another tank due to the plant growth.
Links to more info on NPT's