How to Setup a Low-tech Planted Tank: Planted Aquarium Guide

Non Co2 Low Tech Planted Tank

Setting up a planted tank for the first time can be a daunting task. There is a lot of information out there on the net but there aren't any great "All you need to know" guides with all the information put together in one place. In addition, while there are some great forums on planted tanks out there, you will invariably find a lot of conflicting information being fed to you which makes it even more confusing for a planted tank newbie. While there are some great books for planted tank enthusiasts, the average person looking to setup a planted tank does not have the time to read entire books before they setup their aquariums. This was the motivation for me to put this guide together.

I was a planted tank newbie not too long ago and I spent many months scouring internet forums, books and other resources to make sense of it all. I wrote this article to collect my thoughts and everything that I had learned and also to help other people like me...those who were just beginning to dabble in the fascinating world of planted aquariums. This article should give you all the information you need to understand the science of planted tanks and to allow you to start setting up your own low tech planted tank while keeping algae at bay. The article has grown significantly in size so I have added a table of contents for your benefit.

  1. Introduction
    1. Advantages of Low Tech Planted Tanks
    2. Disadvantages of Low Tech Planted Tanks
  2. Basic Science of Planted Tanks
  3. Things to be wary of
  4. How to Setup a Non CO2, Low Tech, Planted Tank: A Guide
    1. Substrate: Choosing the correct substrate for your planted aquarium
    2. Lighting: Appropriate lighting for low tech tanks
    3. Planting: How to plant your tank during initial setup
    4. Filter: Choosing a good filter for good circulation
    5. Fish: When to introduce them in your tank
    6. Dosing Fertilizers: Weekly dosing regiment to keep your plants healthy
    7. Maintenance: Things to do periodically to maintain your tank
  5. Acknowledgments
  6. Comments and Questions

1. Introduction

Low tech tanks primarily refer to planted tanks which are not actively infused with Carbon dioxide (CO2) and hence do not require all the complicated equipment/paraphernalia/hassle that comes along with using CO2 in your tanks. These tanks use lower light levels than “Hi-tech” tanks and plant growth in general is slower (5 to 10 times) than that seen in CO2 infused Hi-Tech tanks. Whether you choose to go with a low-tech or hi-tech planted tank setup depends on a combination of factors such as your primary motivation/goal for a planted tank as well as the amount of time, effort and resources you are able to spend on your tank. Each method has it's pro's and con's.

The article below describes all you will need to know to setup a low tech planted tank and also compares this method with high tech tanks.

1.1 Advantages of Low tech Planted Tanks

1) No testing and no water changes required (Read: Hassle free! It means that you can leave your tank alone for a week or two and it will still be in great shape)

2) Much lower pruning frequency due to slower growth

3) Very low fertilizer dosing, and only occasionally

4) No risk of overdosing CO2 and asphyxiating your fish

5) If any imbalance occurs in the tank (nutrients, traces, sudden ammonia spike, decaying plants/food), algae growth is much slower than in hi-tech tanks allowing much more time to correct the system for this imbalance.

1.2 Disadvantages of Low Tech Planted Tanks

1) Slower plant growth can be boring for some planted tank owners. If you’re the kind of person who likes pruning and rescaping/replanting very often then you might not enjoy this method as much.

2) It can be harder to grow some types of plants which are very dependent on high CO2 levels for plant growth. However a majority of plants can be grown in these types of tanks, including a lot of the so called “High-light” plants like glossostigma and HC.

If you prefer this hassle free technique for growing aquatic plants and have the patience to wait it out a little longer to achieve your end goals with regards to your aquascaping then read on! If however, you’d prefer a middle-road between low-tech and hi-tech, read my post on Non CO2, Excel tanks.

2. Basic Science of Planted Tanks

Before we get into how to go about setting up your tank using this technique, I’ll briefly mention the logic behind this method. I should mention right away that most of this article is based on Tom Barr’s excellent work ( with planted tanks. I have linked to a couple of relevant threads on his site in the Acknowledgments section at the end of this article.

The lack of CO2 augmentation in a low-tech tank essentially means that the rate of plant growth in such tanks is lower than in hi-tech tanks. Due to the lower growth rates, the rate of nutrient uptake by the plants is also correspondingly lowered. As a result, as in the case of Walstad like tanks, the plants can sometimes even survive purely on the nutrition provided from fish waste and decaying food. The drawback with relying purely on fishwaste and fishfood for nutrients is that the ratio of N,P,K (Nitrogen, Phosphorous and Potassium) in these are skewed out of proportion and can cause a nutrient imbalance in the long run. This can lead to stunted growth in some plants and can also make it very hard to grow certain types of plants which are specifically sensitive to one or more of these limited nutrients.

To overcome this, what we can do instead is dose N, P, K and traces in very small amounts and occasionally (once a week or once in 2 weeks). To prevent any buildup of these nutrients, we can skip the dosing once every couple of months so that the plants use up any excess nutrients in the water column. In this manner we can pretty reliably maintain a non-limiting amount of nutrients in the tank allowing all the plants to grow without any nutrient related inhibition.

It is important to note that high levels of N,P,K, Fe and traces DO NOT lead to algae. Tom has tested this out extensively and has shown that this is simply not true. On the other hand even small amounts of Ammonia (causes could be a mini cycle, decaying plants, fish overloading, insufficient plant mass) as well as fluctuating CO2 levels (fluctuating CO2 levels are thought to signal to the algae spores to start growing) can trigger algae growth. Also In these low-tech tanks the plants and algae are both limited by low CO2 levels. At low light levels and non limiting nutrients, plants can adapt better to these conditions than algae. It is important to have high plant biomass in the tank so that the plants can quickly cycle any Ammonia introduced into the system from decaying food/fish waste.

3. Things To Be Wary Of

Do not increase your lighting! Higher light levels along with low CO2 levels make conditions much easier for algae to adapt to. Plants find it harder to adapt to high-light low CO2 conditions while algae can do much better in such situations. It is for the same reason that many-a-times people are able to fix their algae problems in the early stages by simply lowering their light intensity or photoperiod.

Also make sure that you DO NOT perform any water changes at all! The reason for this is that tap water will have a different amount of dissolved CO2 as compared to what is in your tank. If you perform regular water changes you are effectively causing fluctuations in the CO2 levels in your tank which provides a perfect environment for algae to start thriving in. Only perform top offs for evaporated water. (Warning: This no water change rule should only be used for tanks with high plant density. If you have a tank which is lightly planted and you don't plan on having more than a few plants in it, then stick to doing at least 25% water changes every week. The no water change rule only works if you have enough plants in your tank so that they alone can help cycle the tank and maintain water quality. The same goes for overstocked tanks. While you might risk a little algae from the water changes, fish health is top priority and the lack of decent plant mass might cause a rise in ammonia/nitrite levels which could hurt your fish.) Perform large (60-70%) water changes after any major rescaping where you pull out plants from the substrate and move things around. This is to remove any toxins/ammonia that you might have released from the substrate with all the uprooting. Also do not perform such types of rescaping/uprooting any more frequently than once every 3-6 months.

4. How to Setup a Non CO2, Low Tech, Planted Tank

4.1 Substrate

Setting up your aquarium substrate correctly is very important. In general any type of porous substrate with a high CEC (Cation exchange capacity) such as Flourite, Eco-complete, Onyx-sand, etc. should be great for this technique. It is usually recommended to add a light dusting of peat at the bottom of the tank. Even better, you could use Leonardite (Diamond Black is one brand) at the base in place of peat. It is supposed to be much more stable than peat and doesn’t cause as much of a pH drop as peat can cause if it comes in direct contact with your water column (say when you uproot plants and pull out the lower substrate). Also if possible, definitely introduce mulm from an established tank and filter squeezings from a cycled tank into this newly setup substrate. It will help establish bacteria in your soil much faster.

While some people prefer using soil substrates, and it is certainly a viable option, one has to be wary of some of the risks involved in using soil based substrates. The main problem is that it is hard to know what is in the soil that you are using for your tank. You risk introducing toxins or parasites if the soil is contaminated with them. Also a lot of times soils can keep leaching large amounts of ammonia into the water and this can lead to algae disasters as well as be harmful to your fish. While they are nutrients rich, over time they will lose the nutrients in them, so it is wise to supplement your tank with some additional fertilizers. All-in-all using soil as a component of your substrate is definitely a viable option, but make sure to research carefully and take the opinion of more experienced planted tank enthusiasts before finalizing your soil substrate. Most importantly be aware of the risks and take the necessary precautions to prevent any harm to your tank/fish.

Note – If you wish to use Aquasoil (AS) Amazonia by ADA, then you need to first cycle the soil beforehand and leach out the ammonia before you can use it for this technique. This is because the constant water changes required for aquasoil could potentially cause algae problems. For more info on how to pre-cycle Aquasoil check this link (Links to Internet Archive copy of site since it is no longer functional):

AS is amazing stuff and is definitely the best and most nutrient rich commercial substrate available. Since it is packed with nutrients you could probably get away with no fertilization at all in a Low-Tech Non CO2 technique, save for the occasional dose of traces. However over time as the nutrients in the substrate get used up you will probably need to start dosing some macros again.

4.2 Lighting

Lights play an extremely important role in any planted tank. It is the driving force behind photosynthesis in plants. In the case of low-tech, non CO2 tanks, you need to make sure that you do not go overboard with your lights. Don’t make the mistake of assuming that more lights, kept on for longer periods will make your plants grow better or faster. You will most likely be encouraging algae growth and doing nothing else. Although the Watts per gallon rule is a very general one, it still works well as a basic guideline. For this technique make sure to never go above 2 Watts per gallon, 1.5 WPG being an ideal target. Also remember that we are talking about Wattage of fluorescent bulbs (do not use incandescents…ever! And do not use the “Effective” wattage of fluorescent bulbs for this calculation). Remember that Spiral CFLs are more inefficient so you could lean towards the 2-2.5 WPG regime in their case. On the other hand T5 tubes can be extremely efficient and intense and you should definitely stick to 1-1.2 WPG with T5 tubes. For planted tanks, you should ideally look to have bulbs that are rated between 5500K-8000K. 6500K is a very popular choice.

It is usually advised that when you first setup your tank you should have a photoperiod (i.e., lights-on duration) of only around 6 hours. After a couple of weeks you can bump it up to around 8-9 hours. You probably shouldn’t push it any higher than that. It’s a good idea to buy an automatic light timer (8-10 bucks on Amazon or other retailers) to make sure that your plants are getting the same duration of lighting every day. If you go 10 hours on some days and 6 on others then it could lead to algae issues and also throw the plants off of their “routine”.

4.3 Planting

This is very important - You have to make sure that you plant very very heavily right from the get go. Very heavy means that when you look at your substrate from above, you shouldn’t be able to see more than 10-15% of the substrate. The rest of it should be entirely covered with plants. It can be a little expensive to do this, but it is well worth the hassle. Buy lots of cheap, fast growing stem plants and just stick them into your tank. Try to ensure that at least 50% of your starting plants are the fast growing type. They will help soak up the nutrients in your tank and help cycle the tank by rapidly using up any ammonia from fish waste and decaying matter. Once all the plants get established and are growing well, you can slowly phase out the fast growing plants for other plants that you wish to keep. Always make sure to have a high plant biomass which is healthy. Drastic pruning/replanting can lead to algae outbreaks due to a sudden change in the amount of healthy plant biomass in the tank. Following these guidelines will go a long way in ensuring an algae free tank.

4.4 Filter

Make sure that you have a good filter with adequate flow (At least 10-15 times the tank volume per hour) and also make sure that the output of the filter that flows back into the tank is allowed to flow unrestricted so as to create good circulation in the tank. This helps disperse nutrients uniformly amongst the plants and prevents stagnant areas where plants do not receive nutrients and hence begin to die off giving rise to algae. Canister filters are very highly recommended for planted aquariums as they provide excellent circulation and better filtering capabilities without getting clogged up and negatively impacting flow and cirulation. Also, note that a lot of planted tank folks do not use activated charcoal in their filters as it might pull out some of the nutrients from the tank water. If possible, try getting your filter foam/bio-media pre-cycled by using it in an established tank for a couple of weeks prior to setting it up in the new tank.

4.5 Fish

After setting up your tank give it a week or two to see how it is behaving and if the plants have settled down and have started growing. Also make sure that your water parameters are fine. If this is the case and ONLY if you have also planted very heavily, then you can go ahead and add a couple of algae eaters into your tank. Algae eaters go a long way in keeping your tank spotless and algae free, more-so in such a tank where algae growth, if any, will be very slow and the fish will be able to keep up with it. Otos are regarded as one of the best algae eating fish out there although there are other fish/inverts you could pick too (eg: SAE, shrimps). Some might balk at the idea of adding fish to an “uncycled” tank, but the truth of the matter is that if you have a heavily planted tank in which the plants are healthy and growing, the plants will effectively cycle the tank by immediately consuming any ammonia that is introduced into the system. After 2-3 more weeks if everything is going well and your plants are growing and look healthy you can go ahead and add the rest of your fish. It would be a good idea to add in small numbers over a couple of weeks although many folks have added the entire bioload in one go and haven’t had any trouble.

4.6 Dosing Fertilizers

As per Tom’s recommendations, dose the following once a week or once in two weeks for a 20 gallon tank. If you have a different sized tank, calculate the required fertilizer dose accordingly.

  • 1/4 Teaspoon of Seachem Equilibrium (for traces and Calcium + Magnesium). (1.42 ppm Ca, 0.42 ppm Mg, 3.43 ppm K and 0.02 ppm Fe)
  • 1/8 Teaspoon of KNO3 (Potassium Nitrate) (5.27 ppm NO3 and 3.32 ppm K)
  • 1/32 Teaspoon of KH2PO4 (Potassium Mono Phosphate) (1.61 ppm PO4 and 0.66 ppm K)

You can use Seachem Flourish, CSM+B or TMG for traces instead of Equilibrium although you would need to calculate the corresponding dosage. (For CSM+B, make a stock solution of 1 tbsp or 3 tsp in 250ml. This is roughly equivalent to a Seachem Flourish bottle. 2mls of CSM+B trace solution, 1x a week for a 10 gallon tank should be fine for a low-tech non excel setup) Basically the above solution is roughly equivalent to regular Seachem Flourish. If you choose to use them in place of Equilibrium, keep in mind that you will then need to add Calcium and Magnesium to your tank by some other means. In addition if you wish to use Seachem Potassium, Nitrogen and Phosphorous, then you can use (Registration required) to calculate what dose of your fertilizer of choice you need for your tank size so as to match the ppm levels of the ferts listed above.  ( , are some other fertilizer dose calculators)

It is important to note that since you are not going to be performing water changes it is always better to underestimate the required dosage to prevent a buildup of nutrients in the system over time. If you underestimate and notice any signs of deficiency in your plants you can always increase the dose by a small amount. Also make sure to skip a fertilizer dose once a month or two. This will allow the plants to take up any excess nutrients that might have built up over this time (since we are only approximating how much nutrients the plants need) and effectively reset the system in terms of nutrient levels.

Also, remember that as you gain more experience with low tech planted tanks, you can always try to experiment and tailor your dosing to suit your tank's nutrient needs. You could start experimenting by dosing leaner and leaner till you see visible signs of nutrient deficiency. Once you achieve this, up the dosing amount by a bit and then you should be balancing the nutrient needs of your plants perfectly.

A Note on Purchasing Fertilizers: I would very strongly recommend that you purchase dry fertilizers such as Potassium Nitrate (KNO3) and Potassium Mono Phosphate (KH2PO4) instead of using commercial products such as the Seachem Potassium/Phosphate line. You will save a ton of money by buying the dry fertilizers and 10-20$ of fertilizers can last you almost a lifetime! The only commercial product I would suggest getting is Seachem Equilibrium for traces + Calicum +Magnesium. It is easier than dosing 2-3 separate dry fertilizers for each component of the traces. You can order fertilizers from the following site:

To dose the fertilizers just buy a cheap set of measuring spoons (I have a set for 1/64, 1/32, 1/16, 1/8 and 1/4 teaspoons) and dose the fertilizers directly into the tank (dry). Also don't dose both Macro fertilizers (like N, P and K) and Micro (Traces) at the same time/day as they can react and precipitate out in the tank. It is best to dose them on separate days. If you're really laze like me, you can try dosing them both at the same time but in opposite ends of the tanks.

4.7 Maintenance

Maintenance for low tech planted tanks is fairly undemanding. It involves:

1) Dosing fertilizers once a week or once every two weeks

2) Occasionally skipping the dosing to reset nutrient levels in the system

3) Occasional pruning to ensure good circulation in the tank

4) Gentle gravel vacuuming on occasion to get rid of excess detritus (never do a deep gravel vac)

5) Feed fish every day

6) Do a major (60-70%) water change after any major pruning/rearrangement which involves uprooting plants and moving the substrate around.

Well, that is pretty much it. As you can see from the picture in the beginning of this post, you can create amazing aquascapes using a low-tech technique if you have the patience for it. Additionally it is a lot less hassle and requires a lot less time and effort from your end. Hopefully this article will help you maintain a beautiful hassle-free tank with minimal issues. Good luck with your planted tank endeavors!

5. Acknowledgments:

Most of this article is based on all the useful information I have gleaned from scouring through the forums at Tom Barr’s site, . He deserves all the credit for the content of this article. I’ve just put it all together in one place and added some more stuff to make this more accessible to the planted tank newbie. The original thread related to this technique can be found here :

. Also, if you are interested in an easy way to kick start a beautiful foreground carpet of glosso, HC or Hairgrass, make sure to check this thread:

6. Comments and Questions?

Edit on January 21, 2017 - Well, I can't believe it, but it's been 8 years since I wrote this article and I would never have imagined that this page would ever get so popular and rank well on Google! I'm thrilled that this guide has helped and will continue to help people get into this wonderful hobby. I do owe a sincere apology to the large number of comments that people have left me over the years with questions that were mostly unanswered - My email notifications for comments were ending up in my spam box :-(. I am closing my comments section for now as I don't want to waste other folks' time. Instead, I will happily point you towards excellent communities such as The Planted Tank and Tom Barr's Forums. The former is extremely welcoming to beginners and you will get far better advice and diversity in ideas/thoughts than I could ever hope to provide.

Finally, a small request to you (and congratulations on making it this far down the page! 🙂 ) - I'd highly encourage you to visit any time you wish to purchase something on Amazon. You can select a charity of your choosing from a vast and diverse list and any time you make a purchase through that link, the charity of your choice gets a small cut of the sale (at no extra cost to you!) . I think its a wonderful concept and I hope you do too!

- Sudeep

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