Keeping Live Aquarium Plants

Keeping Live Aquarium Plants

  • Author Mike
  • Creation date
Live plants. Are they really as difficult or take as much time as you've heard? Well, yes and no. If plants are not put into the correct environment they cannot thrive. What would you expect to happen if you placed a full sun plant in total shade in your outdoor garden? If it survived at all, it would not reach its full potential. The same thing is true of aquarium plants.

Let's look at each of the primary factors for growing successful aquarium plants.

The primary factor in the plant trinity is lighting. It can mean the difference between a great success or an agonizing failure. As stated above, lighting will dictate whether you can grow shade or sun plants. In aquatics, plants are classified as low, moderate or high light which roughly translates to full shade, partial shade/partial sun or full sun. The subject of lighting is quite vast with all the available options on the market. Because of all these options a generic watt of light per gallon of water guideline is not valid as 2 WPG of standard fluorescent lighting is not the same as 2 WPG of T5HO lighting.

Many studies have been made to determine just how efficient the various lighting options are. Using digital equipment, Hoppy from The Planted Tank measured the amount of light being output from various types of lighting. While there are many variables, most importantly color temperature output, age of tubes and the quality of reflector, he was able to determine how much light is actually absorbed into an aquarium based on the height above the substrate. The chart below is the result of this research.

Which type of light are you interested in? A low light, no fuss planted tank? How about a high tech tank? Regardless of which type of tank, we need to look at what will be needed to balance the light and keep algae away.

There is a direct correlation between lighting and fertilization. The more light, the faster the plants will grow and the more fertilizer will be required. When too little or too much fertilizer is added to a tank fish can be negatively affected an algae will take advantage of any surplus.

In very low light most tanks do not require the addition of fertilizers. Plants grow slow enough that the fish waste and weekly water changes are enough.

The easiest form of fertilizer to dose is liquid. These fertilizer formulas can be single component or compound mixtures. Seachem Fluorish is one of the more common liquid forms. This product line has many options. The base component is their Comprehensive formula which is a balance of trace elements and very low levels of macro elements (nitrogen, potassium, phosphorus). In my experience this formula works best in a low-moderate light set up. In a 90G high light tank, cost will average $20 per month.

One of the biggest downfalls of liquid fertilizers is that they cannot be fine tuned to each tank's need. When a tank is heavily planted, heavily stocked, understocked or under moderate to high lighting customizing the fertilization schedule can be the difference between a healthy, thriving planted tank and one that is riddled with algae.

Dry ferts are commonly used in tanks that are at least 55G or high light tanks. Dry ferts are purchased as separate compounds that can be dosed dry or mixed with water. The basic components include:

Potassium Nitrate (KNO3)
Mono Potassium Phosphate (KH2PO4)
Potassium Sulfate (K2SO4)

Plantex CSM + B

The beauty of dry fertilizers is that you can customize to your tank's needs. Just like everything else, your tank has its own unique needs. For example, I have very high levels of phosphate in my tap water and I grow some iron demanding plants. So in my situation I have completely dropped the phosphate component and can increase the iron to keep my tank happy. Dry ferts are also very economical. A $20 purchase can last about a year or longer with a 55G planted tank.

For the heavy root feeding plants (swords, crypts, vals, etc) there are root or substrate fertilizers. I use Flourish Root Tabs as they are well balanced and dosed every 3 months; and placed at the roots of the plants. Many with low to moderate lighting use root tabs to ensure the plants receive the required nutrition.

CO2 Supplementation
Carbon is the basis of all life forms; and is required for plant growth. Being submerged, aquatic plants often need help. In low light tanks plant growth is so slow that carbon supplementation is not required. Weekly water changes are enough to maintain the required carbon levels. In moderate or high light/high tech tanks carbon supplementation becomes a requirement.

The most common liquid carbon form is Seachem Excel. The active ingredient is glutaraldehyde. Many aquarists purchase Cidex or Metricide 14 and mix with water to attain the 1.5% concentration found in Excel to keep the cost down.

DIY CO2 is a homemade CO2 generator that uses yeast and sugar. Here is a link to information that already exists in the forum: Instructions for Setting up a DIY CO2 System.

Injected CO2 can be very costly to set up, but is quite economical with running costs; and will pay for itself in a few years. There is a semi-automatic setup which is turned off/on by a simple timer; or a fully automatic setup which relies on a pH controller to turn the CO2 gas on/off based on pH levels.

Everything really just boils down to how much you can afford and how much time you want to spend with your tank each week.

One other thing I should mention...substrate. Plants will grow in the more expensive substrates just as well as in plain gravel or sand. Again it boils down to personal preference and your budget.

Adding the Plants
Now that you have the three major components covered (lighting, fertilization and CO2) it's time to find plants that will grow in your tank. And there is nothing better than research. If you have a low light tank, stay away from the higher light plants. If you are brand new to plant, just like with fish, start with the easy to grow beginner plants.

Here is a short list to help get you started:

Low Light
Anubias varieties
Cryptocoryne varieties
Java Fern (Microsorium pteropus)
Water Wisteria
Vallisneria varieties
Green Temple (Hygrophilia corymbosa)
Bolbitus (Bolbitus heudelotii)
Blyxa Japonica
Dwarf Sag (Sagittaria subulata)
Tiger Lotus (Nymphaea zenkeri)

Moderate Light
Sword varieties
Hygrophila varieties
Water Sprite
Luwigia varieties
Marimo Balls
Bacopa varieties

High Light
Most bright red/pink/purple varieties

Seachem Flourish Products
Seachem Root Tabs
Seachem Excel vs Glutaraldehyde


First release
Last update
5.00 star(s) 7 ratings

More resources from Mike

Latest reviews

Really helpful
This was very informative! I am trying to establish a planted tank and I love it when I see a lot of growth. Tho you!
Excellent, detailed info. I'm new at this fishy stuff (one yr.) and was considering switching from plastic "plants" to live. You did a perfect job of talking me right out of it and saved me from making an expensive mistake. Too much work for me right now. Thank you so much! I do appreciate it.
Great article for care of live plants
Great article. .thanks for the info
  • Lon
  • 5.00 star(s)
Great, thank you Mike.
This is a must read for anybody that is new to live plants.
Top Bottom