[FriendsNotFood]

Hey everybody!
I know that there is already a very comprehensive list of low-light plants. But having read through that entire thread, it seems as if a lot of the plants on it are up for debate and some of them are only on the list because they can do well in low light with extra CO2.

I'm interested in plants that absolutely do not need supplemented CO2. As in, they won't just "survive" without it, they'll grow without it, albeit not as large or fast as they would with it. My tank has about 2.5 WPG lighting, mineralized topsoil, Excel, and no CO2, and I'm weighing all my plant options so I thought this might be a useful low-tech list to have. My apologies if this already exists somewhere else on the forum.

 

[HypnoticAquatic]

any low light plant will grow with no additional co2 they just grow slower thats the only advantage of co2 is faster growth so if your tank is set up properly any low light plant will work plain and simple, now as ur survive vs grow thats all just a timeline basis no co2 will just grow painfully slower so either buy more to have a already filled in tank or add co2 if your impaitent to see full results theres not much else you can do its nature.

 

[BBradbury]

Low Light / No CO2 Plants

Hello Friends...

Most aquatic plants will grow very well with lighting in the 1 to 2 watt per gallon range. I have less than one watt per gallon in my tanks and have quite a few different plants that grow extremely well in standard pea gravel and organic potting soil with a little liquid fert dosed a couple of times a week. Nothing fancy, you just have to get the right plants.

I like to experiment with different substrates and liquid ferts to see what grows and with a few plant exceptions that are more demanding, most will grow in lower light if you can manage to get the plant close to the light source. Attached are some pics of my low light, low tech experiment tanks.

With the lighting you have, you can grow more than enough different plants to fill a large tank.

B

 

[Java Moss]

Java Fern tied to lava rock.

Started out with two bought at Petsmart two years ago, threw it in my son's 20 gallon long with stock light and a few community fish...now have well over 10 rocks, each with JF growing strong and proud.

 

[kamikazi]

just to be clear, technically plants cant live without CO2.

 

[talontsiawd]

I have yet to find many plants that I cannot grow without injecting co2. They may not grow quickly, or reap the color of having high light, but they can be grown in low enough light where co2 is not required.

There is a catch to this though. You are going to find a huge difference in a 12 in tall tank verses a 24 in tall tank. These are 2 of my tanks. Conventional wisdom says I would need both high light and CO2 to accomplish this. But, it's a 5 gallon and a 10 gallon, they are short tanks. I couldn't do this on a 37 high, for example. But, no CO2 on either of these tanks, not much more than a spec of algae. Ever:

http://www.plantedtank.net/forums/planted-nano-tanks/143598-5g-low-tech-low-maintance-dutch.html

http://www.plantedtank.net/forums/t...bum/103106-10-gallon-low-tech-rock-scape.html


I guess my point is, there are factors that will allow you to grow much more than the next person with proper planning. My HC, which often is said to not only need high light but say CO2 is necessary, was pearling in the second link daily. No ferts, excel, were needed on a regular basis either.

 

[FishFarmer]

Any plant that is a low-light plant will require less CO2. Less light=less energy to drive the photosynthesis reaction, thus less carbon is needed.

 

[FriendsNotFood]

Talonts is clearly using some sort of voodoo and going against all conventional wisdom so now I'm really confused. The only thing I can conclude is that it's like he said, the height of the tank makes a big difference, therefore nano tanks are much different from larger tanks.

The thing I still don't understand is this... what happens when you have high light and no CO2? Tons of algae? Is that the only drawback? Or do the plants just die off because they're not getting enough carbon but too much light? Talonts' tanks seem to prove that you should have as much light as you can even if you don't have CO2, which is not what most people would say.

 

[talontsiawd]

Talonts is clearly using some sort of voodoo and going against all conventional wisdom so now I'm really confused. The only thing I can conclude is that it's like he said, the height of the tank makes a big difference, therefore nano tanks are much different from larger tanks.

The thing I still don't understand is this... what happens when you have high light and no CO2? Tons of algae? Is that the only drawback? Or do the plants just die off because they're not getting enough carbon but too much light? Talonts' tanks seem to prove that you should have as much light as you can even if you don't have CO2, which is not what most people would say.

I wouldn't say so much that you can only limit it to nano tanks. I refused to take people's words on things. Such and such "needs co2", such and such needs "high light". I tried things out and most plants don't need as much light as people want to believe to look nice. I actually often have more problems getting great colors in my high tech tank.

One major thing is that the slower something grows, in my experience, the more color it seems to be able to take on. I am not purposely limiting growth but I am doing nothing to enhance it, no CO2 in those tanks. But, I am also doing no ferts either. This has been my experience.

Lastly, you need to have some idea of what will be balanced as well. If you are a beginner, you may struggle with the tank with HC I had, for example. Not because it was hard to do, I just had a good idea of how much light I needed. I was very patient letting it grow out.

I know I just started a journal for my 5 gallon but that is 1 year and a few months old. I didn't just plop in plants and call it a day.

 

[JasonG75]

just to be clear, technically plants cant live without CO2.

Agreed...its our LIGHTING that makes the Co2 requirement. However there are some plants (HC) that just wont grow unless there is suplimented co2. If HC was the only plant in the tank, then you could probably get away with Excel, but if there were several plants then Co2 will be required.

 

[talontsiawd]

Agreed...its our LIGHTING that makes the Co2 requirement. However there are some plants (HC) that just wont grow unless there is suplimented co2. If HC was the only plant in the tank, then you could probably get away with Excel, but if there were several plants then Co2 will be required.

Again, HC, pearling, with no regular use of Excel. The interweb says you need CO2 (or can get by with excel)

 

[FishFarmer]

The thing I still don't understand is this... what happens when you have high light and no CO2? Tons of algae? Is that the only drawback? Or do the plants just die off because they're not getting enough carbon but too much light? Talonts' tanks seem to prove that you should have as much light as you can even if you don't have CO2, which is not what most people would say.

High light with "no CO2" (be careful when saying "no CO2"; there's still CO2 there, or else algae wouldn't even grow) results in an algae farm. A plant that is a fast grower and requires high light, would most likely die off due to the lack of CO2. Now a plant that is a slow grower and requires less light, in that same tank, probably wouldn't die because it requires less CO2 than the high light plant--in other words there is a sufficient amount of carbon for the slow growing, low-light plant and not a sufficient amount of carbon for the fast growing, high-light plant. Now this is all taking algae out of the equation, which is next to impossible. In a tank with high light and no carbon being added would result in an algae bloom, which would also deplete the water of nutrients, preventing the growth of any plants in the aquarium--so even the low-light plants would most likely die off too.

Make sense? lol. All you really need to know is high light without sufficient carbon and nutrients is just asking for trouble.

 

[Sharkfood]

The thing I still don't understand is this... what happens when you have high light and no CO2?

Fast growing plants will often show deformed growth. Some won't. Algae is the biggest problem with too much light.

You can even get some very light pearling like in the picture above without the use of CO2. Pearling in a high light, CO2 injected tank is substantially more intense.

Less light= less demand for CO2. Even plants that grow well in low light usually need, or at least benefit from CO2 in a high light environment. CO2 is usually beneficial at all but the lowest light levels, but isn't usually required below a light level that I am going to arbitrarily call "medium light".

 

[plantbrain]

My tank has about 2.5 WPG lighting, mineralized topsoil, Excel, and no CO2, and I'm weighing all my plant options so I thought this might be a useful low-tech list to have. My apologies if this already exists somewhere else on the forum.

You can grow anything you want......Excel takes the place of CO2 for the most part there.

I'd use even less light personally.

Are you avoiding CO2 gas ............for what reason??? If it is a lack of knowledge and having not used it.......you might reconsider. This is typical reason for folks avoiding it like the plague.

If your goal is more lower maintenance, then non CO2 offers really nice advantages. Some of my tanks are non CO2, and this means no Excel as well.
I do not fall on either side, I advocate both equally.

Most all plants are low light plants in aquatic species, I know of no high light requirement plant. Adding CO2 will reduce the light required even.........lower.

So if you want to minimize light and energy waste, this is the way to do it. Non CO2 systems have issues with plant= plant competition for CO2, this is the strongest evolutionary process/factor I can think of, that and start photosyntheisizing before the other species(so light and CO2 uptake).

In a non CO2 tank, there's limiting CO2 available, the one who first gets it, will win out. When we add CO2 gas, now any group of plants can grow in the same tank now without competition for CO2. If we allow the plants to grow emergently, then there's also no CO2 competition.

This it Table 1 from Tropica's web site:

http://www.tropica.com/advising/technical-articles/biology-of-aquatic-plants/co2-and-light.aspx

As you can see, in each and every treatment matrix presented, there is GROWTH, the only difference is the growth RATE. Management wise, no CO2 and high light is asking for algae issues, in this study, the Riccia was sterile, so not algae where present. They concluded that mix efficacy of plant growth was achieved with low light and high CO2.

We also have poor comparative ways of measuring light, what sounds like high light may VERY WELL NOT BE HIGH LIGHT. This is where a PAR meter used to measure light can be useful. My tank at 1.5W and 3 ft away from the plant has the same PAR light intensity as an ADA Light 24" away and 2.7 W/gal.

If we just did W/gal, I would be way off.

With a light meter, I can see they are the same.

 

[FriendsNotFood]

Well I think this is starting to make sense now. There's a number of reasons why I don't want to add CO2 but it's mostly because I want to keep the tank relatively low-maintenance. This is my home tank and I'm not home for more than a few hours each night.

As far as lighting, I have 4x24W lights directly over a 36 gallon tank so that makes it 2.75W per gallon, right? Does that make the light too high if I'm not going to supplement CO2? I plan on adding floating plants to reduce the lighting a little.

One final question...has anyone had luck with lilaeopsis mauritiana in a low-tech setup? I have a bunch that looks like it's struggling and I'm waiting to see if it's going to make it.

 

[FishFarmer]

As far as lighting, I have 4x24W lights directly over a 36 gallon tank so that makes it 2.75W per gallon, right? Does that make the light too high if I'm not going to supplement CO2? I plan on adding floating plants to reduce the lighting a little.

If they are T5HO lights, then I would say that is too much for a tank without pressurized CO2. I have a 48 watt T5HO over my 29 gallon tank and I'm not using pressurized CO2, just 5mL of API CO2 Booster daily. Some people cautioned me that the 48 watt T5HO was even too much light, but I have reduced the photoperiod to 3hrs in the morning, and 4hrs in the afternoon, and so far I have not had any algae issues. So if you do use that light over your 36, I would say leave it on for 3hrs then off for at least 4, then on again for 3 or 4. Also, like you mentioned, the floating plants will help cut down on the intensity of the light. You can also use a screen top to reduce the light, it also prevents fish jumping out of your tank too.

 

[JasonG75]

Again, HC, pearling, with no regular use of Excel. The interweb says you need CO2 (or can get by with excel)

TOTALLY agree with this...IS there any other plants in the tank competing for Co2?

 

[Hoppy]

24 watt bulbs generally means 2 foot long T5HO bulbs, and 4 of them, with typical very good reflectors is very high light on a 36 gallon bowfront tank. Unless the light is about 3 feet or more from the substrate you don't have low light. Even if you have a light with poor reflectors you still have high light with the light sitting on top of a 36 gallon bowfront. And, it is very hard to succeed with a planted tank with that much light and no CO2.

 

[FriendsNotFood]

Yup, the lights come with a ton of reflectors. The guy I bought the lights from tried to convince me it wasn't going to be too much light I'm thinking I'll just cut the light in half. The fixture comes with a timer that lets me control the lights two at a time, so if I set the timer to have two of them on for the first half of the day and the other two for the other half, that should do it. Will that then be TOO little light? I want to keep it as bright as I can without needing CO2.

 

[plantbrain]

Well I think this is starting to make sense now. There's a number of reasons why I don't want to add CO2 but it's mostly because I want to keep the tank relatively low-maintenance. This is my home tank and I'm not home for more than a few hours each night.

As far as lighting, I have 4x24W lights directly over a 36 gallon tank so that makes it 2.75W per gallon, right? Does that make the light too high if I'm not going to supplement CO2? I plan on adding floating plants to reduce the lighting a little.

One final question...has anyone had luck with lilaeopsis mauritiana in a low-tech setup? I have a bunch that looks like it's struggling and I'm waiting to see if it's going to make it.

Okay, now we can help you better with management.
Excel dosing can be done........and if you miss a fay or two, no biggie.
You can do a few water changes here and there, say once a month and be fine also, dosing will be easier, a modified EI routine is easy: 1/4 dose but only 2x a week is enough for such a tank.

That's a pretty easy routine, water change once a month etc.

I'd use about 1/2 the lighting, I have a tek 4x 24 W over 70 Gal and a 60 Gal at 3 ft away from the bottom= a ton of light.

Foreground plants take 2-4 weeks to get going.
It looks like they just sit there during this time.

Patience.

After all, you do not have a lot of time to devote correct? If you have faster growth= more labor and work right?
You cannot ask for rapid growth and no work