Planted aquaria are a complicated matter. They require combining good animal husbandry, a green thumb, and a thorough understanding of the chemistry in the water column to create a thriving environment. Fortunately, almost anyone can begin to learn how to set up a planted aquarium. Let’s dive in and I’ll show you the basics.
Step 1: Understand the Basics of a Planted Aquarium
There’s more than meets the eye to a planted tank. You can just start adding fish and plants to a freshwater aquarium and hope that your “clown-puke” gravel works out, but you’ll end up wasting money and lives.
Instead, you’ll need to get the basics down.
Ecosystems, Not Enclosures
Unlike animals like rats or bearded dragons, you’re creating an entirely new ecosystem when you start setting up a fish tank. This holds true regardless. The difference is that in most tanks, the only visible animals are the fish, and few people give any thought to the microfauna in the filters and soil.
That’s not the case with a planted tank. Everything that you place in the tank has a purpose, from the smallest snail to centerpiece fish like Discus.
Ideally, you’ll be able to create a system that only needs minimal input from you. A well-matured planted tank can often get away with minimal water changes. Instead, the focus is on the food and light input in the tank.
So, as a general rule, you’re going to deal with the following:
- Bacteria: The foundation of a healthy water column is thriving microfauna. These little guys keep the nitrogen cycle moving. When they’re in full effect can completely mitigate the harmful effects of ammonia and nitrite compounds in the water.
- Invertebrates: Shrimp and snails. While you may need to be careful about those you select, the truth is that often you’ll end up with thriving snail populations just from buying plants. Shrimp are more specialized but can help to keep waste and detritus down to a minimum.
- Plants: Either the star of the tank or the background depending on how you set things up. Your plants consume the nitrates that result at the end of the nitrogen cycle. Making them thrive is the key to maintaining the ecosystem as a whole.
- Fish: The fish that go into your tank to accompany the plants. They’ll end up generating the bulk of the bioload in a tank, which fuels the nitrogen cycle. Planted tanks are usually either species tanks of larger specimens like Angelfish or community tanks with one or two central fish. Choosing them takes a bit of knowledge.
Your goal with a freshwater planted aquarium is to make all of these smaller components of the whole thrive. It’s not as hard as you think, but it all starts with changing the way you think about tanks.
The Nitrogen Cycle
The nitrogen cycle in a tank is easy to understand for most people. It’s just that they’re not aware of it in the first place.
- Ammonia (NH3) is created directly as waste by fish and also indirectly from leftover food which rots. Nitrosomonas sp. bacteria break this down. Ammonia is extremely toxic to your animals.
- Nitrites (NO2) are also quite toxic. They’re broken down further by Nitrobacter sp. bacteria.
- Nitrates (NO3) are the end result of the process. These are tolerated at high levels by most fish and plants that are available for sale. Plants uptake nitrates as nutrients alongside carbon dioxide(CO2) to continue their growth.
A tank that has the bacteria in place to take care of the current ammonia load would be considered “cycled.” If you add livestock too quickly, you can overwhelm the current bacteria levels and create an imbalance.
A freshwater test kit is a requirement for tanks. While more advanced kits are often useful, you need to be able to test for the above just to make sure your fauna are safe.
As a general rule, both ammonia and nitrite levels should read as undetected by your kit before you add any more livestock. Anything above 0ppm of either is undesirable. Any detectable level of ammonia is toxic, while nitrite ranges of .5ppm or higher are unacceptable.
Nitrates, on the other hand, are considered acceptable in the 5-10ppm range. Anything over 20ppm is cause for concern but there are ways to manage it as long as the nitrite and ammonia levels are bottomed out.
Some Basic Terminology
To avoid explaining terms over and over, let’s also go over some basic terminology before we begin to create an actual plan for your planted tank.
- Bioload: This is the amount of waste a given fish or animal produces. Some animals(like goldfish) will produce more waste than their size indicates. Others(like Oto catfish) have a negligible load in larger systems.
- Aquascaping: The overall aesthetic design of a tank. There are a few dominant styles we’ll discuss shortly in Step 4.
- Low-tech Tank: These tanks have a focus on using less light, less equipment, and less overall input. They’re an environment that requires minimal outside help by design.
- Biofilm: The buildup of protein and matter that occurs on plants in aged tanks.
- Substrate: The bottom layer of the tank, whether sand, gravel or something else.
Step 2: Decide on a Tank Size and Get Your Equipment
The first step is to decide how large of a tank you’d like.
Small tanks take up less room, but many newbies to the hobby make the mistake of assuming they’re easier to manage. Nothing could be further from the truth: small tanks have much less “wiggle room” when it comes to the water column.
Large swings in pH, temperature, or even waste levels occur much more quickly in small tanks. Many fish can acclimate to a wide variety of conditions. But, few can tolerate large swings in water parameters even if they’d be able to survive easily in the new condition.
I recommend at least 20 gallons for a first tank. A 40-gallon wide tank or 55-gallon long is even better if you have room for them. The absolute minimum that a completely new aquarist should try to manage is a standard 10-gallon tank. 10 gallons will be a bit touchy still but careful monitoring of water quality will allow you to manage.
Seamless tanks are also ideal but the increased cost doesn’t sit well with most people. They’re also harder to find a hood for, which creates problems in some cases.
Filtration is the most important piece of the puzzle. Without a filter of some kind, it’s really not possible to keep a tank running long term with any appreciable amount of livestock. Goldfish bowls are great for cartoons but in the real world, they kill fish.
There are three basic types of filter:
- Hang-on-Back Filters: Often called HOBs, these filters hang on the back of the aquarium. They’re easy to service and the main issue that people have with them is keeping them level.
- Canister Filters: A canister filter has an intake and an output hose and passes the water through a large amount of filter medium. They can actually add considerably to the total water in a system when used with smaller tanks. They’re expensive and harder to service but offer the best filtration compared to flow rate.
- Internal Filters: These have suction cups and sit on the side or back of the tank. They’re best used for an extensive aquascape where hiding equipment is a concern, but it’s hard to find a good one due to their simplicity of design.
For a newbie, I recommend going with an AquaClear HOB filter. They’re middling in price, run quietly, and are remarkably easy to take care of.
Filters are rated for a certain amount of gallons, but I’ve found that running 1.5x-2x what the box says it will take is a good idea. The only time it’s not is if you’re intent on keeping Betta, Gourami, or other fish that don’t do well in high flow tanks.
Under gravel filters are… useless for a planted tank and iffy for anything else. Avoid them.
Heaters and Chillers
Your heater doesn’t need to be anything special. As long as it holds temperature, you’ll be fine. Most brands work just fine, don’t get worried about stories about heaters “running away” that you’ll find in reviews and on forums occasionally.
Chillers are sometimes needed for high lighting tanks or those who live in particularly hot climates. They’ll hook into your filter in most cases, just find something that works with your filter.
The ideal temperature range for a planted tank runs from 70° to 80°F. Most fish thrive around 72°F. Anywhere from 72° to 75° will allow you to keep the majority of tropical fish healthy and happy. Some fish do require warmer temperatures, however.
Now we’re going to talk about something which determines the plants you can put in a tank.
Your lights will end up being the determining factor, but they’ll also represent the largest expense for your tank. And your electric bill. In many cases, they’ll use much more electricity than the rest of your equipment combined.
Those factors are what make low tech tanks so popular.
If you’re looking to create vivid, multi-colored aquascapes, you’ll need more lighting. Plants like Red Ludwigia are popular, beautiful, and fail miserably without higher lighting.
Aim for at least 2W per gallon for your tank. That’s what I would consider the bare minimum for healthy plants, although some will go a little bit lower for true low-tech tanks. For more colorful plants, 3W-5W is better.
Using full-spectrum lighting, those ranging from 500K to 6500K is ideal. I prefer to use T5 bulbs despite the advent of LED lighting. They’re compact and you can fit quite a few bulbs even over a smaller tank. LEDs are great for spot-lighting but that’s a more advanced technique.
Lastly, you need to have a CO2 generator of some sort, especially in tanks with higher lighting. While it’s true that some CO2 comes from your fish and even from rotting plant matter… CO2 is important.
There are many commercial systems on the market, ranging from those that use a fermented yeast base to those that use compressed tanks. The latter are expensive, bulky, and the best way to control CO2. Some enterprising folks have even captured the CO2 from making beer or wine. You’ll need to make sure you have a check valve in place for any kind of fermentation as the byproducts getting into the tank is a terrible scenario.
CO2 tanks can be adjusted. Too much CO2 can overwhelm your fauna and create drastically increased plant growth. Too little and you’ll barely see any growth at all. Each tank is different in this regard.
Step 3: Pick and Place a Suitable Substrate
The bottom of your tank is the first major decision you’ll need to make when you’re getting ready for setting things up.
There are a couple of considerations here. The important thing is that you don’t just lay down an inert gravel or pebble substrate and hope it works out since these contain no nutrients.
Nutrients in Substrate
Many substrates now come with nutrients and are a great base for plants. Root tabs are a pain and liquid fertilizers are often expensive, so you’ll want to make sure that you start with the good stuff.
I prefer Flourite, which was pretty much the original, but there are a ton of great brands available these days.
The texture is up to you, but as a general rule, sandy substrates allow for a wider variety of bottom-dwelling fish.
Color has a big effect on your aquascaping and the overall look of your tank. Most people prefer something darker which allows the plants and fish to stick out more.
For biome tanks seeking to replicate a natural environment, you may want to go with something lighter. But, as a general rule, go as close to black as possible for an aesthetic look.
Layering doesn’t need to be an advanced problem. One of my personal favorites was to lay inert sand over a layer of Flourite, which contains a lot of nutrients. This allows you to avoid the need for root tabs and liquid fertilizers for three to six months.
Sandy surfaces tend to cloud the water more. For a beginner, the easiest way to do things is to just lay down an impregnated substrate that comes in chunks. Heavier sands with larger particles are also available and some can also have nutrients contained within them. These are great for fish like Corydoras Catfish, which like to search the bottom.
Lowtech tanks sometimes have bottoms comprised of potting soil covered by around an inch of play sand. It’s a cheap option but it can cause some screw-ups in the water column during water changes. You’ll need to find a way to get water in the tank without disrupting the soil. It creates a touchy bottom, but it allows for great nutrient distribution at a low cost.
Grading the Bottom
At this stage, you may also want to grade the bottom. For a showy finish, many will raise the back of the aquarium and drop the substrate to the level of the frame as it goes forward.
Creating raised portions is often used in Dutch-style tanks as well. Simple plastic dividers are an excellent option for maintaining them; then you can simply grade the substrate downwards for that portion.
Japanese style tanks tend to depend on rocks to create raised portions and hills. We’ll discuss the styles in the next step.
Step 4: Choose and Place Your Plants
Your plant choice and placement is primarily an aesthetic concern. For breeding tanks that aren’t for show, for instance, you can just add a ton of floating plants as a nutrient soak.
Come up with a strategy before you begin adding plants, adding them blindly often results in a haphazard mess instead of a great looking tank.
The most important thing is to know your plant types. From there, it’s possible to begin aquascaping.
Stemmed plants are quite varied. They range from Ludwigia sp. with smaller leaves to the broad-leaved Rotala sp. They’re the primary source of colors other than green in your tank.
When aquascaping with them, it’s best to create bunches of stems. Most will readily re-stem, and you can cut down your initial purchase into 2”-3” chunks and plant them in the substrate. They usually do best along the back of the tank.
For species with red or orange coloration, it’s important to make sure they get sufficient light. Many species will either lose their colors, fading to green, or wilt away without it.
Once rooted properly, these plants will thrive and grow quickly. Keep them trimmed back to a manageable level and you’ll be fine.
Swords and Vallisneria sp. are the most common rosette plants for aquaria. Swords have broad leaves, while Vallisneria have a grass-like effect.
These plants are generally easygoing and great for low-tech tanks. The Amazon Sword, for instance, is perfect for beginners and nearly impossible to kill as long as a bit of care is taken.
Best practice for planting these plants is to clip the roots down as much as possible without damaging the taproots. You can then place them in the substrate to just below the “bulb” under the plant. Once rooted, they’ll grow quickly.
The most common plants that grow from rhizomes are Anubias sp. and Java Fern. Both are readily available in most pet stores and they add a lot of character to a tank.
The rhizomes will need to be placed above the substrate. Most people tie them to rocks or driftwood. Use light fishing line for the best results; it won’t decay prematurely and is mostly invisible. Some use cotton thread, which will rot away but generally lasts until the plant has rooted itself properly.
Rhizome plants are slow-growing but don’t give up hope. Some will need additional shade if you’re running a tank with high lighting. Anubias, in particular, tend to prefer shaded areas of the tank, so tying them to the underside of jutting rocks or driftwood is perfect.
Floating plants are useful for creating a cover for fish as well as shading the lower portions of the tank. Most grow extremely quickly, so I don’t recommend them for smaller tanks. Plants like Hornwort can grow an inch or more per day in a well-established planted aquarium.
Hornwort and Anacharis are the most common species found. Things like duckweed are also capable of growing in an established aquarium but need even more care. While the effect is often nice floating plants do require quite a bit more maintenance than you’d think.
Ground covers are low-growing plants that create a moss, grass, or other “cover” effect over the lower areas of the aquarium. Despite the seeming simplicity of them, ground cover plants are much harder to work with than most aquatic plants.
If you’re a beginner and need the ground cover effect then Dwarf Hairgrass is the easiest way to go.
Just be aware that ground covers require high lighting, high CO2 levels, and adequate care to truly thrive.
There are three primary styles of planted tanks when you look into aquascaping:
- Dutch: Dutch-style tanks are less common these days but can be truly beautiful. They’re built like a garden with raised beds of plants. They’re usually dominated by stemmed plants and rosette plants, and vibrant colors are grouped together. The plants are kept closely cropped, and it has a beautiful, but clearly artificial, effect.
- Japanese: These tanks usually evoke a miniature landscape. They do so using low-growing plants, mosses, and rocks as decor. They usually rely heavily on ground-cover and rhizome plants.
- “Jungle”: These tanks are generally chock full of plants and untrimmed. They’re low maintenance and often decorated with both driftwood and rocks. Plants are allowed to grow large and along the surface and it creates a pleasing home for your livestock.
Beginners may, or may not, concern themselves with the different styles of tank. As time goes on, you’ll begin to understand them and I feel that a “Jungle” tank is the best way to go. They’re low maintenance and are one of the best ways to keep your livestock happy.
Once you have your plants set up and add water, you’re ready to begin adding your animals.
Step 5: Add Your Fish and Invertebrates Gradually
To begin with, you’ll need to only add a few fish. My recommendation is to add only two or three fish per 20 gallons. Use schooling fish or bottom-dwellers to start and test the water daily.
You’ll generally see an initial spike in ammonia and nitrites before the bacteria begin to convert things. Don’t add any more fish until these levels are unreadable and test the water daily. If ammonia or nitrites look high, an emergency water change may be in order to dilute the waste material.
Each time things level out, you can add some more fish until you’re stocked. I recommend keeping things down to one inch of fish per gallon of water in the tank. You can sometimes get away with overstocking a heavily planted and well-established tank. That said, it’s not a good idea for a beginner who doesn’t know exactly what they can get away with.
What About Invertebrates?
Small snails can be added immediately. These include Ramshorn snails, pond snails, and other small, quick-breeding species. You can also add a larger snail such as a Nephrite or Mystery with each time the tank levels out.
Look for Malaysian Trumpet snails. They’re a great addition to any planted tank.
You’ll often get them as hitchhikers on plants if you’re purchasing from a local fish store and they’re extremely beneficial to your tank. You’ll rarely see them as they stay in the substrate most of the time, but the aeration created by their tunneling helps promote healthy plant life.
Shrimp should be added only once the tank is fully cycled. In tanks of 20 gallons or more, their bioload can be safely ignored, but in smaller tanks, you may want to only add three or four total.
Most dwarf shrimp will breed prolifically, but your fish will eat the majority of the fry. Don’t get too worked up about the babies getting eaten, you’re setting up an ecosystem and it’s going to happen.
Hot Tip: If you can find them, keep an Assassin Snail or two in a bowl with a few plants. When snails get out of hand, it can be unsightly and moving these carnivorous snails into the tank for a couple of weeks will clear up any excess numbers. Remember to remove any Apple or Nerite snails before adding them, however.
Are Any Fish Not Suitable for a Planted Tank?
Some fish, no matter how you try to balance things, are nearly impossible to keep in planted tanks.
The foremost among these are cichlids. Any cichlid bigger than 2” or so is completely unsuitable for a planted tank. These intelligent, lively fish do things like tear plants up out of sheer boredom. Some dwarf cichlids, like the German Ram, do fine in planted tanks, but things like Oscar, Jack Dempsey, or any of the colorful African cichlids are a no-go.
Larger varieties of Plecostomus, such as the common Pleco, aren’t good for planted tanks either. They’re simply too powerful and tend to tear things up when startled.
Oddly enough, Pirhanas do quite well in planted tanks when they’re large enough. In this case, it’s their look-alike, the Pacu, which is unsuitable. These herbivores will take care of any plants in their vicinity without discretion.
As a general rule, it’s more sensible to keep small, non-aggressive fish as a community in planted tanks. Some of the larger species which are suitable include Discus and Angelfish. Most fish of that size will end up wreaking havoc on your aquascaping, however.
As long as you follow the above guidelines, you’ll be fine. It’s mostly a matter of balancing the size and aggression of your fish to keep any of them from getting hurt.
Step 6: Maintaining Your New Planted Aquarium
Maintenance is the difference between a decent freshwater planted aquarium and a great one. Once the tank has livestock and plants in place, it’s a waiting game to get the tank where you want it.
Even a lush jungle is going to need a haircut once in a while. Trimming back plants is done for two reasons.
The first is just aesthetic. Keeping plants pruned in the proper shape for your desired look
The second is to remove dead leaves before they begin to rot in the tank. This is the important part: shed leaves that sit around are bad news for your water chemistry.
In general, you should trim your plants as follows:
- Stem Plants-Try to trim at a 45° angle directly above the growth node. Any trimmed pieces can easily be replanted if you’re looking to make the thicket bigger or to go for a more dense look.
- Rhizome Plants-Trim dying leaves off the plant and cut things back where you don’t want them. Cutting the rhizome can create a new plant but only attempt it with a well-settled plant, or you may cause more stress than needed.
- Moss-Just cut them back and remove whatever you don’t need.
- Ground Cover- Rarely requires trimming, but thinning them out and removing any dead foliage is standard.
- Rosette Plants-Trim off dying leaves at the base and remove them from the tank. Runners can be removed, replanted, or left in place at your discretion.
Remove all dead foliage. It may not cause any serious problems but it will help to raise the nitrates in your tank. Any dead or dying plant leaves should be removed immediately.
Keep Feedings Small
Feeding time is essential for your planted aquarium. Without the nutrients provided by your fish’s waste, there’s very little in the water to help plants grow.
That said, you want to feed only what can be eaten in a couple of minutes.
The only caveat to this is livestock that eats very slowly. Some bottom-dwellers and animals like African Dwarf Frogs are slow to eat. You should still monitor how much food they’re eating and cut down on waste.
Wasted food is bad for water quality, which means it’s also bad for your fish and plants.
Water changes are just a part of keeping aquaria. Use a siphon and switch out some of the water regularly, right?
Well, kind of. I suggest keeping up on your water changes regularly during the first couple of months that your tank is running. These initial changes should be about 25% of the total water volume of the tank.
Later you can check the nitrates in your water to know if you need to do a change. If you’re getting above 15ppm, it’s time to do a water change. Otherwise, many people find they can just top off the tank and get on with life.
If you’re topping off regularly, there’s one more big thing you need to do. That’s to get a water hardness test kit. If the dKH(degree of calcium hardness) rises over 10-11, you need to resume water changes until it’s lower. In areas with hard water, it’s recommended that you mix half-and-half with RO or distilled water to keep hardness to a manageable level in the first place.
Water quality is your top concern. As long as the water is good, everything else is negotiable.
Creating a thriving planted aquarium is rewarding and much easier than most people think. Once you have the basics down, it’s easy to slide into the artistic side of things if that’s where you’re headed, or you can just enjoy your beautiful aquatic garden.
It’s just a matter of knowing the basics and planning ahead. Are you ready to get started?