Starting Your Planted Tank

Last update: October 17, 1998

1. Plan Your Approach

The first step (and the most difficult) is to decide what kind of planted tank you want. Oh, sure, gorgeous, just like the photos in "The Optimum Aquarium" is a wonderful goal, but be realistic. The more structured and aesthetic a planted aquarium is, the more work it is to maintain. Don't for a minute think that the perfectly aquascaped tanks you see in photos remain that way for more than a day. Plants grow and they don't care much about their appearance. If you want an aquatic water sculpture, be prepared to do daily sculpting.

The best advice is to look on the Web, in books, in magazines, at fish store displays and among your friends to find a style of tank you really like. Ask pointed questions about the effort and expense to set it up and the effort and expense to maintain it. Don't depend on verbal descriptions like "My plant tank Rules!" and "My plants are gorgeous!" Look at pictures or the real thing. Judge for yourself. Decide up front if you will have the discipline to maintain the tank as required. And don't mistake "high tech" for "low maintenance" -- they are totally different animals.

Realistically assessing your abilities to create the desired tank is essential to success. Setting lofty goals for yourself if you aren't able to carry them to fruition is the first step to failure. It's better to start slow and learn the essentials instead of investing in an expensive and frustrating disaster.

In our case, we spent from 1986 to 1991 learning the ins and outs of planted tanks before we went off the deep end with our "Dupla-spec" 90 gallon tank. By the time we began planning it, we knew our abilities and were able to create a very successful display tank.

Once you have decided on a course of action, it is wise to document your ideas and ask the advice of others. An excellent source of expert and friendly critique is the Aquatic Plants Digest mailing list.

2. Approach Your Plan

The best way to screw up your carefully laid plans is to rush into things. Spend some time gathering your equipment. It is agonizing to go slow once you have your goal in mind, but it is best.


We have found it very useful to do "wet runs" of the equipment before actually doing the real set up. Get your aquarium, stand, lights, filtration, plumbing and substrate heating (if used) assembled and try things out before you add the substrate, plants and fish. Make sure your plumbing doesn't leak before you reach the point were you can't easily start over. Add water to the bare tank and check water circulation by adding a sodium bicarbonate mixture to your filter -- it stays milky long enough to visualize the circulation patterns. Set up your CO2 system, adjust KH and set the CO2 flow to produce the right pH. Check your heaters to make sure they are set to the right temperature. Adjusting and tuning the equipment is so much easier when you don't have expensive plants and fish in the water to worry about.

Stuff to Avoid

It is very tempting to go overboard on filtering, especially with the wealth of stuff out there. The only things you want in your filters are mechanical and biological media. Do not add a bunch of chemical filtration paraphernalia like activated charcoal, phosphate absorbers, heavy metal absorbers, zeolite, ultraviolet sterilizers and the like. The plants will take care of this function naturally since most of the "bad" things are needed for plant growth anyway. This will greatly disappoint your fish store manager, but hang tough.

Likewise, save your money and pass on all the wonderful chemicals that sound so helpful.  No water conditioners, no bacteria starter cultures, no pH buffers. Your aquarium is very capable of maintaining good chemistry without a lot of commercial assistance.


As you get close to the big day, arrange for your starting stock of plants. It is critical that your new tank is densely planted with fast growing plants right from day one. The conditions in the new tank will be very unstable and will be ripe for algae. Having thriving plants sucking up nutrients right from the start is the best way to prevent algae from getting a foothold.

If you have other plant tanks, let them grow out so you can use the excess to stock the new tank. If you have nearby friends that have plant tanks, try to beg or buy excess plants from them. The best thing for a new tank is to get plants that are healthy and thriving and that are adapted to the kind of conditions you are going to provide them.

Plants from fish shops and from mail order are a second best option. Plants in fish shops are usually not grown in optimum conditions and are probably dying as they sit in the shop's tanks. It's a rare store that has proper lighting, CO2 levels and fertilizers in their plant holding tanks. You may also find that the plants in the stores have been grown emersed and are not yet adapted to a submersed existence. Mail order plants may be of good quality (you only find this out by experience or word of mouth) but the two to four day shipping time don't do them much good.

For your initial planting, select plants that are fast growing and don't worry too much about aesthetics. The best plants to start with also tend to be the least expensive plants, helping out your already strained budget. Good starting species are Hygrophila (especially H. polysperma), Bacopa, Rotala and Ludwigia. All these do very well with good light and CO2. Plants to initially avoid overdoing are Crytocoryne and Anubias.

Some people recommend dipping new plants in a weak bleach mixture to kill off algae and algae spores. I do not recommend this as it also affects the plants to some degree and will slow down their adaptation to the new tank. Try to ensure the plant are visibly algae free or came from a relatively algae free environment, then trust your algae eaters to do their job.


Some algae is inevitable in a new tank and the best defense is a variety of algae eating fish. Black Sailfin Mollies are excellent algae eaters if they are not fed regular fish food and they are fairly robust and can easily tolerate the unstable initial conditions. After a week or two, more sensitive algae eaters can be added to augment the mollies. Recommended varieties are Siamese Algae Eaters (Crossocheilus siamensis), various otocinclus sp. and Farlowella acus. It is wise to have multiple varieties of algae eaters since they tend to specialize on certain algae types. With three or four types, no algae is safe.

Do not be concerned about high ammonia or nitrite levels during the initial break-in. A heavily planted tank will show very low peaks of ammonia and nitrite as the bacteria colony establishes itself. The plants themselves consume ammonia in the form of ammonium (NH4++), preventing any major problems.

3. Ready! Fire! Aim!

Hopefully, you won't end up doing as the title suggests! For a humorous account of what might go wrong, read the SLAG setup in the Kirb archives.

Assuming the tank and equipment are up and ready to go, the following steps are appropriate for Day One.

A Case Study (of the wrong way to do it!)

When we first set up our 90 gallon tank, we had the noble but misguided goal of buying all new plants to avoid introducing any residual algae from our other tanks. Although it sounds logical, the bigger risks are not getting decent plants to start with and maybe introducing new and exotic algae that you don't know how to deal with. We also didn't pay attention to the "fast growing plants at first" rule.

We ordered $200 worth of plants from a now defunct mail order supplier. We ordered a few show plants - large Echinodorus and Anubias. We ordered other decorative plants and only a token few fast growers. We had the tank all set up and running the night before and waited in anticipation for the UPS truck. It came on time and we eagerly tore into the box. We were highly disappointed :-(

We had paid $5 extra for a styrofoam packing box but they didn't use one. The plants were wrapped in newspaper, put in plastic bags and packed in a plain cardboard box. All the taller show plants were actually folded in half before they were wrapped and were bent and misshapen. Some of the more delicate plants we ordered were frozen mush. Most of the plants were fairly small and in poor condition. We were heart-broken :-((

We planted anyway, hoping against hope that the plants would recover. The tank looked so barren after we planted $200 worth of plants that we added plants from our other tanks anyway. The dismal result is shown below:

... It did get better...

4. Tough It Out

Two important things happen in the first month after you set the tank up: the nitrifying bacteria colonize the tank and filters and the plants adapt and get established. During this time, the water conditions in the tank are very unstable as nutrient levels vary and myriad life forms discover the wonderful new wet spot you have established for them. The best advice is to sit back and enjoy the show. Trying to tamper with anything at this point in time will only cause trouble.

The most common "problem" observed at this stage is new tank syndrome.  You will notice the water initially has a hazy white appearance. This is due to a bacteria bloom in the water and is harmless and natural.  Your new gravel came from places unknown and contains lots of dormant critters that washing will not remove. Getting the gravel wet revitalized them and they will grow for a short time. Most likely, they will die from lack of food or they will become food for higher order critters. Do not use any of the clarifying chemicals sold for this purpose. It's pointless and a waste of money and will only contribute to a longer period of unstability.

You may also observe that the plants don't seem to be growing much. Don't panic. Two things are at work here. First, the plants may be starved of nutrients if they came from other than great conditions. Plants can concentrate and store many trace elements for "hard times" (such as being in a fish store holding tank) and they may replenishing their supply in lieu of using the nutrients for growth.  Secondly, the plants may be growing  and you just can't see it because you're looking so darn hard!  Take lots of photos of your new tank and you may be surprised just how much is happening.

It is very important to not feed the initial algae eaters. Make them scrounge the tank for anything they can find. Algae will be springing up just like everything else and needs to be controlled. If the fish are not distracted by real fish food, they will be more likely to search out and destroy the tender young algae shoots.

During the first month, the nitrifying bacteria will be establishing colonies everywhere in the tank (not just in the filter). If you want to monitor the cycle by measuring ammonia, nitrite and nitrate, make sure you have accurate test kits. The traditional cycle is longer in a planted tank and the peaks are much more subdued. There are two reasons why this is true:

By the way, recent research has found that the bacteria responsible for converting nitrite to nitrate is not Nitrobacter as is commonly believed. They don't know what species it is, but they know it's not Nitrobacter.

Don't change water during the initial break-in period. There is no good reason to change water and fresh water will only add to the instability by refreshing whatever caused the instability in the first place.

Be sure to properly fertilize the plants. They are trying to grow rapidly and need all the nutrients they can get (in proper proportions, of course -- don't over do it).

If you monitor iron levels, you will note that it will probably be high initially due to the fresh laterite. We typically see levels of 0.5 mg/l. This is OK, since the nitrifying bacteria use iron to grow and the plants can concentrate and store excess amounts. You will be shooting for 0.1 mg/l of iron in the long run.

After a couple of weeks, conditions should be stable enough for other algae eaters.  Remember, a variety is good!

... A little later

5. Adapting to Your New Aquarium

After a month or two, you will find that your new planted tank is coming into its own. A careful observer will be fascinated by all the stuff going on in the system. If you keep a log book, review your observations regularly. If you don't keep a log book, shame on you!

By now, plants should be ready for their first trimming and perhaps some rearranging. You may find some plants that didn't do well for whatever reason and need to be replaced.  You may be surprised at the growth patterns of some plants that may affect your aquascaping scheme. You may want to try some slower growing, more decorative plants for special effects. For whatever reason, you'll probably be mucking doing Real Aquatic Gardening. If you find you don't enjoy this, you might reconsider what you are doing.

One thing that worries new aquatic gardeners is just how to prune and arrange plants. Some are very reticent to move plants or even prune them.  Don't worry -- plants respond well to "tough love".  Don't be afraid to uproot plants and move them around. We are only careful about moving plants with massive roots systems like Echinodorus or plants that grow in large masses like Cryptocoryne and only then because it makes a mess when you pull them up!

You can prune stem plants two ways:

Pruning rosette plants usually entails pulling the older leaves off at the gravel level.

This is the time to start adding the primary fish to the tank. The biological filter is established and the system should now be very stable. Add fish slowly, though, so the nitrifying bacteria can adapt to the new load slowly.

You may find that different types of algae are coming and going as the water conditions pass through stages favorable to different species. Don't panic. Let the algae eaters do their job.  If you find one algae type is getting a toehold, perhaps this is the time for another type of algae eater. We usually see a soft, velvety green algae at about this period. Farlowella acus are very good at controlling it. You also may notice long, stringy algae threads that don't attach securely to the plants. This is usually a sign of too much iron. We've not seen any algae eaters eat this type but it can be easily removed by twirling a toothbrush in it.

Monitoring nitrates will give you an idea of how often to change water. We like to keep nitrates at around 10 mg/l on average. If you have a lower fish load, you may find that nitrates will consistently read zero (make sure you have a good test kit!). If this is the case, you may find you need to add nitrates, usually in the form of potassium nitrate. It is recommended that there are at least 5 mg/l of nitrate in a planted tank. If nitrates are too low, the plants won't be able to grow and remove the phosphates that are in the water, leading to algae problems.

... Even later!

6. The Daily Grind

Maintenance is covered fully in another section, but I would like to list what is typical for an established planted tank.




Every couple of years