definitely. folks over on plantedtank.net use these rules and guidelines a lot. the latest hype over lighting is PAR and distance. Tom Barr and Hoppy talk about this all the time. Hoppy has done lighting all his life, and even worked for NASA, so ill take his word on lighting. and Tom Barr, well he's just the american equivalent of Takashi Amano, even more knowledgeable i'd saylujor;4327957;4327957 said:
Originally Posted by nipat
Most people here in Thailand refrain from using low light.
They are afraid their stem plants will go leggy.
Is 30 umol OK for stem plants?
I don't have experience in stem plants except
heteranthera zosterifolia which doing somewhat OK
(no leggy) in low light.
Yes, many are under this assumption, not just in your country, but most other countries as well.
I think this will take a long time to remove such perceptions such as excess nutrients or PO4 will lead to algae.
These same folks where also the same ones that suggested that adding excess increased the risk of algae when the hypothesis failed on it's own. But they do not see the correlation between high excess light and algae?
Rubbish.
If you already have higher excess light, then reducing it is easy and offers no risk because you can simply revert back to high light.
If they are unwilling to test, then they need to not offer people advice based solely on their inexperience and ignorance, no matter how nice their aquarium might look, if they have not tried it and done so a few times, then something is wrong there.
So this risk issue is not realistic at all. At worst their plants get leggy, pale etc. They bump the light up just a little bit, then again till they have non leggy growth and good color. This seems to be about 30-40micromols for most plant "high demanding" species.
If the growth is compact etc and nice color, and I have low light, then something else must be at the root of their leggy growth other than just light. There must be some other cause they have not accounted for.
I've measured and used a PAR meter to answer how low we can go within reason. So it's a fairly concrete range, number, parameter.
It takes 1-2 weeks for most plants to gear up and switch to lower light. If you start off with low light, then there is rarely any issue. Plants need a lot of Carbon and Nitrogen to gear up for lower light. If these are added in non limiting amounts, the plant should adapt very well.
Many aquarist think less is better with respect to nutrients, often waste time testing and fiddling with nutrient ppm's, hardly pay attention to CO2 as much as they likely should and then want to add too much light and do not bother to test light. This is backwards.
Then complain about stunted tips and algae.
Regards,
Tom Barr
And some good discussion on another thread regarding other common myths in the hobby, especially surrounding EI and other forms of dosing:
Confusion about EI and other mythsAs this method has become popular, it also has had growth pains.
1. It was never meant to be applied rigidly.
2. It is a simple concept, provide non limiting nutrients without having to test to do so.
3. Adding non limiting nutrients provides the plants with optimal nuterients so folks can rule out deficiencies
4. Precise plant nutrient Deficiencies are not known for most every aquatic plant. This requires a high level of testing and things like fish food, sediments and other potential confounding factors come into play.
5. If you have lower growth, lower light, then you can make safe assumptions like using less nutrients, again, refer to #1.
6. Algae are not nutrient limited in aquariums with fish and plants. Argue this all you want, but you need to research and see what types of nutrient levels will limit algae. They are extremely low and any fish waste and plant decay, leaching etc is more than enough to supply algae with all they need.
7. 90-95% of all algae related issues are due to improper use of CO2.
8. 90-95% of all algae problems are related to improper use of CO2.
There is a good reason to repeat this because folks will forget and blame the nutrient dosing method(and this issue is not limited to just EI, every other dosing routine has the same issues).
9. Measuring CO2 carefully is not easy. It varies, it's influenced by circulation a great deal, it can change 10X in concentration in less than 30-45 minutes.
No other nutrient can change this rapidly, nor is critical to every other nutrient. Algae take advantage of this variation to germinate and establish.
Be very careful in assuming you are 110% positive you have enough, instead, rule out everythign else first, then go about tweaking CO2 and do so slowly, never rush or get impatient.
10. In general, less light is better than more for every method using CO2.
This reduces CO2 demand, if you use higher light, consider having methods to reduce it, control it if any issue come up.
11. EI rules out nutrient deficiencies. While this can rule them out, many find that after adding non limiting nutrients, they still have issues. EI is not solely about nutrients, if the CO2 demand was limited because there was not much PO4, now the CO2 demand is greatly increased. If the CO2 is not also increased to account for this change, then it can lead an aquarists to incorrectly assume that it is the PO4 that is causing the plant or algae issue. However, it is a secondary effect. If the CO2 was controlled correctly in the test, then the algae/plant issue would not have occurred. Such error/s in logic cam lead to false assumptions/conclusions.
12. Make as safe assumptions as you can.
13. Test if you want along with EI. Some do so to get a feel for their aquarium, then no longer test if they are within the target(theirs or EI's etc) ranges. These are choices you make/trade offs and you decide if they are worthwhile for you.
There is no rule that says you cannot test. I suggested testing along with water changes in the past(see 1996-1997 list of levels of parameters thread here). However, testing correctly is not been one of aquarist best traits
These are cheap test kits and with poor resolution, so it is wise to calibrate any test kit before relying on any data obtained from their results. Even 10,000$ lab test equipment is calibrated, this way we know the results are accurate.
14. EI is not based on flowery language, perception or marketing schemes. It is not based on faith. It does not disparage other methods. The results are testable, the concept come from PMDD and the math is even in there as well, I simply posed a few graphs.
15. EI is specific to the water column source of nutrients, however water does diffuse into sediments and can become a source of nutrients to the roots as well.
This does not preclude aquarist from using root sediment sources as well in conjunction with water column fertilizers.
16. Ratios. Hot topic and few really understand anything about it and why it does not matter. Epstein and Bloom are two very well respected researchers on this topic and it really gets down to limiting vs non limiting levels much more than a ratio (see their text: Mineral nutrition of Plants, Principles and Perspectives, 2005). Ratios can save the farmer spending 1000$ on fertilizers and reduce their runoff waste, however, aquarist do not have issues here and the cost is insignificant. Still, a relative range of ratios is not bad either, but with the wide range of species kept and each one having their own set of growth rates, nutrient demands, this seems very difficult to apply in a general way.
17. RR or Redfield ratio, often discussed and cited and folks make a mistake in mass vs atomic number of atoms. A ratio of atoms, number, is 1 P for each N according to marine algae in Redflied's paper.
This is not mass.
P is 30.97 grams per mole
N is 14.01 grams per moles
To convert to mass, you need to multiply N by 2.2, now the RR is 7:2 1, or about 10:1 for NO3/PO4.
Still, this is just what is available from upwelling in ocean systems and is typically under extremely high light, full sun etc. The system becomes limiting after prolonged algae growth.
This is radically different from what occurs in freshwater systems where aquatic plants are involved. FW plants have different ratios, different nutrient sources and cycling, as well as being able to concentrate nutrients from their external surroundings at a much high gradient internally.
18. Inhibiting levels of nutrients, the upper bounds. Generally, this is from osmotic conditions, too much salt basically. Hoagland's modified solution is very rich and is a non limiting nutrient solution. EI is just a similar idea but on the lower end for aquatic plants, above the limiting ranges but not nearly as rich.
Hydroponics and Hoaglands solution has a very long history and test/research background for support.
EI is no where even remotely close to these levels of inhibition.
19. Less light = less demand for nutrients. You can go too far and get so low plants will not grow no matter what the CO2/nutrients, however, it's a very useful way to control the rates of growth for an aquarium and also to control algae until the conditions are corrected. Many have issues with CO2, so using less light makes targeting a good stable CO2 level much easier than say higher light intensity. Thus limiting light makes the most logical sense, not nutrients and CO2 for algae control, for stability, for CO2 issues/nutrient issues, for control of growth rates, for less electrical use, reducing heat, reduction of any and all waste.
20. If the CO2 is not properly added, then EI, nor most any method(unless it limits a nutrient so much that CO2 decreases) will help you. Severely limiting PO4 can reduce CO2 demand, but can be difficult to keep doing. Might as well just use less light, since that's where all growth starts.
You see?
Lots of CO2 talk, very little about nutrients............
Regards,
Tom Barr
co2 can be used in any scenario. but yes, when go into high lighting it become a requirement and not an option. this is because the intense light levels are causing plants to demand more co2 and ferts.Pyramid_Party;4328019;4328019 said:
This is somewhat true... I do not think that you should base your lighting on what lighting level you wish to have, but rather, your lighting based on what plants you intend to keep. While lighting does drive some algae to grow out of control, it is not the only thing. A lack of co2 can, regardless of lighting (when talking about high intensity bulbs), as can an excess of phosphates or nitrates. No one factor alone can stop algae. You must balance macro/micro nutrients, co2, lighting, and the plants them selves. Running 1000W of LED with matching co2 and ferts to keep everything in check, still will grow algae if you only have a handful of java ferns. Planted tanks are always a balancing act. But having the light be the limiting factor can be dangerous in new systems, as the plants become more established, they will grow faster. If the light isn't enough, then the plants can die, or not grow fast enough to keep algae down. Utilizing only a select number of lights while starting and having the ability to go up will help in the long term. My old 135 ran 4 54W HO T5, and 4 24W HO T5 bulbs. This tank was dosed with dry ferts and co2 constantly, and never had many algae issues, except on vacations.jcardona1;4328057;4328057 said:Ok, so I want to share some info I found some time ago on another site. It deals with one of the most common myths and misconceptions in the planted tank hobby, some even go as far as calling it a disease that many hobbyists suffer. And that is high lighting.
Folks are under the impression that freshwater plants need stadium lighting in order to grow properly. They try to stuff fixtures meant for saltwater aquariums on a freshwater planted tank and then wonder why they only thing they can grow is algae. Corals and freshwater plants are totally different animals, literally. Corals need much more intense lighting. This is why you see ridiculous 6x or 8x bulb T5HO fixtures. Try that on a freshwater tank and see what happens
2x T5HO bulbs over ANY tank will pretty much give you high lighting (unless you're dealing with a truly giant tank). I would even say raise the fixture a few inches to reduce the intensity. That's it, just two bulbs. Running anything more is asking for algae troubles. And with these two bulbs you better have the CO2 and ferts to match. If you're not adding CO2, you have no business running T5HOs, it just isn't needed. You'll get better results and have less problems if you stick with PCs or normal output bulbs, when not using CO2.
Tom Barr takes this a step further by saying we should use lighting as the limiting nutrient, and provide ample amounts of CO2 and ferts. Because another myth, is that people think excess ferts will cause algae problems. This simply is NOT true. And limiting lighting makes perfect sense. I've said it time and again, lighting is your gas pedal; it drives the plant growth in your tank and drives the demand for CO2 and ferts. The more light you have, the more your plants need CO2 and ferts and the harder time you will have keeping everything balanced and the algae at bay. The less light you have, the less demand for CO2 and ferts. This will ultimately lead to a tank that's easier to maintain, and in the long run, ENJOYABLE. Because let's face it, if you're not enjoying your tank you're doing something wrong.
With that, the things you should take away from this is - reduce your lighting intensity, bump up your co2 and ferts, and enjoy. I'll let Tom Barr take it from here. These are few excerpts from his thread. Full thread can be found here: http://www.barrreport.com/showthread.php/6972-The-light-limiting-growth-management-method
And some good discussion on another thread regarding other common myths in the hobby, especially surrounding EI and other forms of dosing:
not that they're more important, as all three are equally important. what it's basically saying is that lighting is the easiest to control, and co2 is the hardest.Pyramid_Party;4328306;4328306 said:
