[Zapins]

This thread was started as an offshoot from another thread, see below for details.

In a nutshell this thread is about the term deficiency. I hear people using the term all the time for things that I do not personally consider a deficiency. I hear "CO2 Deficiency" multiple times a day and I believe the usage of this term is incorrect to the extreme.

To me, the most meaningful definition of deficiency implies the plant is harmed by the lack of a particular nutrient. A deficiency causes a disease like state that leads to injury, damage or death. If nothing bad happens then it is not a deficiency.

Having less CO2 slows growth but growth is still perfectly healthy and the plant will still grow to the same size and shape as those in CO2 supplemented conditions, therefore it is not deficiency but rather a speed of growth regulator. I believe a CO2 deficiency can indeed occur and would present as the plant completely stopping all new growth and dying. Since true CO2 deficiencies are difficult to make happen, even in a lab, there are few papers describing the symptoms of an acute deficiency.

In a true acute (as in 0 CO2) the CO2 deficiency plant dies due to no sugars to use and no carbon for maintaining cells. A chronically low level of CO2 results in slow growth but no damage an no other negative health problems.

This is the original post that caused this thread to bud off from the original thread. From here:http://www.aquaticplantcentral.com/forumapc/algae/89126-organics-analysis-12.html#post665006

Cavan,
There are more effective and safer ways of supplying carbon to bacteria in an aquarium than gluteraldehyde or polyacetalgluteraldehyde. That stuff is used as a disinfectant after all. Reef folks have been using white vinegar, vodka, and our Reef BioFuel to supplement carbon in their systems for years. I'm fairly certain our planted tanks aren't carbon limited though. There are enough biogenic sources of C and preferential uptake of inorganic C by plants leaves plenty of organic C available for bacteria. With abundant N and P I highly doubt nutrients are limiting microbial growth; if any limitation exists. That's one of the points I was trying to make when comparing natural systems vs. aquariums. In nature bacterial/phytoplanktonic influence can be great, but not so much in our aquariums.

Phil I agree with you, I really don't think our tanks are carbon deficient at all. I think this has been hyped up way too much. People add so much CO2 that their fish die and still get accused of not having high enough CO2. Its ridiculous.

 

[Yo-han]

Re: Organics Analysis

I think this is a good discussion point for a side thread How do you otherwise explain the simple fact that plants can grow 5-20 times faster with CO2?

http://www.tropica.com/en/tropica-abc/basic-knowledge/co2-in-the-aquarium/co2-effect.aspx
http://www.tropica.com/en/tropica-abc/basic-knowledge/co2-and-light.aspx

 

[Zapins]

Re: Organics Analysis

Not sure what you mean exactly Yo-han.

People use the term "deficiency" far too often. From what I can piece together the symptoms of carbon dioxide "deficiency" are basically slower--but still healthy--growth.

To me, a deficiency does not mean slower growth it means visible detrimental signs like chlorosis, necrosis, twisting, holes in the leaves etc...

A deficiency is not always the limiting nutrient. Just because CO2 makes plants grow faster does not mean that you cannot grow healthy plants with CO2. That is basically the same thing as saying the entire world's biomass is CO2 deficient and therefore unhealthy because the CO2 levels aren't 1000+ ppm which is optimal for most plants.

If slow growth is a sufficient symptom for a deficiency then maybe we should be terming everything with deficiency, if your plants grow slowly because its too cold then it should be called a temperature deficiency. And if the plant grows tangled leaves because it was floating at the top of the tank then we should call that a substrate deficiency, or possibly a gravity deficiency since the plant doesn't know which way is up as it bobs around in the current.

 

[niko]

Re: Organics Analysis

But Zapins, that is exactly how most folk in this hobby see the problems - "something is missing, find it and add more of it". After jacking up the CO2 there is only a fertilizer deficiency that can explain everything.

To most folk there are only 4 variables: ferts, CO2, light, and water changes. When was the last time you heard someone asking about plant growth issues and wondering if their filtration is ok? Or flow. Or substrate. Or temperature, pH, or oxygenation?

Water changes can't help your plants grow. Holes on the leaves are not going to disappear if you change water. You need to add K in most cases. But as we recently learned from a 1990's article the tank cleanliness affects the algae growth. Could be that if affects plant growth too because apparently it affects how the biochemical processes happen. Ok, most folk change water on a regular basis and never think much more of it. So here's the article again. Apparently in the ancient 1990 is was not enough to fill a glass box with gravel and water and plants. Things needed to happen in a certain way too. Too old and too complicated to be true. Scroll down to "A new look at mass balance in the aquarium":
http://www.prirodni-akvarium.cz/en/index.php?id=en_algaeTOC

Ok, so water changes are not going to make your yellowing plants turn green, everybody knows that. Next are lights. Usually people have "enough light" so they can grow anything they want because "more is better". "Enough light" is a questionable thing too because PAR is funky indeed, especially if you want to get on both the "cheap" and the "LED" train. So usually people assume they have enough light because they got "Brand X" or because the PAR is "Z" according to the seller that measured it through air and right under the bulb. So that's the end of it, no discussion needed. I actually think that often it is too much light because if the tank is not functioning properly the light that would be ok otherwise quickly brings algae. No, too much light does not bring algae but funny thing - you can slow or stop algae if you decrease the light.

Water changes and (lotsa) light out of the way leaves CO2 and ferts. A "deficiency" of either one or both. Crank up the CO2 till the fish start to suffocate and then back off a little. Never mind bacteria, biofilter, and accumulation of stuff that they are not processing which halts what not processes in that glass box. Jack up the CO2 as high as possible! Finally you can get to the most exciting part of this hobby - figuring out what fertilizer is missing. Funny thing - people believe they do something wrong and they indeed do something wrong. But it is not what they think it is because the 4 things described above don't describe a tank fully.

The horribly deficient Japanese tanks grow stems out of this world. N=1 and P=0.05. We are all sure the Japanese lie about these values. Because we have all heard of Amano's big tank that had 4' tall Rotalas with perfect leaves top to bottom which is impossible if you do not run CO2=30 and loads of ferts in the water. Most of us believe that a plant really feels better knowing that there are 1.75 ppm of P more to eat while gobbling on the first 0.25 (kind of like me and a gallon of ice cream vs. me and an ice cream cone). Most of us believe that in 2013 a glass box full of chemicals is better than a glass box full of clean water in 1990. Water with not enough chemicals is the definition of a deficiency. You should know that, Zapins!

And by the way - today I heard that CO2 falls apart slowly. 100 years if I understood that right. That CO2 is to blame for things in the ozone layers that most of us don't believe are bad. We use just a little bit anyway - like 5 lb. every few months... Crank up that CO2 and watch your plants grow to their full natural potential! Actually even better than in Nature.

 

[Tugg]

Re: Organics Analysis

I'm loving this disscussion. All I think Zapins is saying is that he doesn't like the term deficiency, and would prefer something like "limiter" for things like temp, light, and CO2 since a incorrect quanity of them doesn't really harm the plant, it only slows it down.

However, when a fert is insuffecient for the current growth rate, it does harm the plant. Showing a clear deficiency.

Basically he's just saying that you can't you look at a plant and go "That plant is CO2 deficient." But you can say it's limited by CO2, which is just fine for many people with low tech tanks. They may not want the rapid growth.

 

[Phil Edwards]

Re: Organics Analysis

Deficiency is simply the lack of sufficient X needed for chemical reactions to proceed. Even with biology things often come down to chemistry. Mineral nutrient deficiencies in plants are often expressed in ways we can see; such as chlorosis or deformed tissues. In an ecosystem deficiencies might be expressed as reduced primary production. For example, if an aquarium ecosystem has enough light to produce 5 grams dry weight plant mass per square foot, but only receives enough C to produce 3 gDW/ft^2 then the ecosystem is deficient in carbon. That may not mean the plants grow poorly or show symptoms like chlorosis, but the system is deficient none the less. We can also express systemwide N deficiency as being N limited.

Even light can be deficient. If there's not enough incoming energy for the plant to maintain its tissues, not grow but simply maintain, then the plant will starve and die. Anything at or above the plants' basic needs for irradiation could, and probably should be, considered a luxury excess that drives the system's biogeochemical processes/metabolism. Slow growth due to low light doesn't indicate a deficiency. It indicates a rate limiting supply of incoming energy as long as it's enough to meet the plants' basic metabolic needs. Lack of any other material in sufficient supply to meet a plant's light-driven metabolic needs is a system wide deficiency. If increasing supply of carbon causes plants to grow faster, more robustly, thicker, or what have you, then that means the system's carbon deficient. That's where "jacking up the CO2" comes into play.

The idea that water changes are a supply of nutrients may or may not be true. It depends on the nutrient load of the water being added. In some places the water supply may have sufficient concentrations of X nutrient to meet the system's needs. In some places it may not. Regardless, doing water changes can be a very useful tool for controlling nutrient loads and rectifying imbalances. Please don't forget that we're horticulturists in glass boxes. We're taking plants and trying to grow the most beautiful/healthiest/largest/what have you plants we can for visual appeal in a closed system. By that definition we *must* supply nutrients to the system somehow. Whether that be via the substrate, water column, or both; our confined "domesticated" plants require us to provide them with nutrition they wouldn't otherwise get.

Having seen some ADA tanks up close and personal, I can say for certain that they are not typically deficient on the whole, but they don't look as good in person as they do in the pictures. I did see signs of some nutrient deficiency in some plants, especially epiphytes that don't have roots in the substrate. What does that mean? They should add stuff to the water column. Yup. That's right. Time to toss some NO3 and PO4 in the water. They have algae issues too, even after a year of being set up. *GASP* Still, on the whole, they looked great. I've seen some US hobbyists tanks that looked better *SURPRISE!*, but they still looked damn good.

Sorry, I got on a bit of a tangent didn't I?

 

[Tugg]

Re: Organics Analysis

Then he's right. The whole world is CO2 deficient (from a plant perspective) since a higher ppm would increase rates. Also, hasn't this whole discussion has been a tangent from the OPs original simple request for samples.

If this is technically correct, then I'd prefer to be wrong. I would prefer to say the system is CO2 limited. I feel "deficient" implies something is wrong (not sustainable), while "limited" implies something is held back (sustainable).

 

[Zapins]

Re: Organics Analysis

Tugg I think you understand me perfectly. I feel people are misusing the term in general. To me, the most meaningful definition of deficiency implies the plant is harmed by the lack of a nutrient. A disease like state that leads to injury, damage or death must occur in order to be a deficiency. Having less CO2 slows growth but growth is still perfectly healthy and the plant will still grow to the same size and shape as those in CO2 supplemented conditions, therefore it is not deficiency but rather a speed of growth regulator.

But you are right we have strayed from the OP. I think I will make a new thread from our last few posts in order to continue our debate and declutter Jeffy's thread. If that is OK with you Jeffy?

 

[Tugg]

Re: Organics Analysis

This of course isn't saying someone CAN'T have a CO2 deficiency. A perfect example is when the CO2 runs out and then all the carbonate is consumed. Then the water acidifies and starts causing other problems.

 

[Zapins]

Yes, CO2 deficiencies are definitely possible, but they are rare and occur in unique situations. Not when someone is injecting 3 bps into their tank and others are telling them they have a CO2 deficiency just because the plants aren't growing as fast as is maximally possible. That is not a deficiency. Even having no CO2 addition on your tank and moderate lighting does not give you a "CO2 Deficiency." The plants are limited, not deficient and diseased.

Acute deficiencies like the one you mentioned Tugg cause death. When you see scaling on your plants (biogenic decalcification) that is a clear sign the CO2 in the water has been virtually completely depleted. Not all plants can use carbonates, the ones that can are more hardy.

 

[niko]

Here's a real life observation that I have observed in at least three tanks which I had the opportunity to observe during a prolonged period of time.

Very short light period. 2 hours only. 96W Power Compact 1" from the surface of the water of a 40 gallon breeder tank. So 22 hours of darkness (room with no windows) and 2 hours of strong light. No fish and no fertilizers. Inert quartz as a substrate but only 1/2" thick. Very light CO2 misting and sluggish inefficient water flow. All plants where fine, even stems but all grew slowly. HC floated on top of the surface and made tiny leaves but never died.

One day the CO2 ran out. In 3 days the tank changed dramatically. Plants started to melt very fast. Even Crypts didn't like the no-CO2 situation but the HC somehow stayed alive probably because it was more of an emersed than submersed growth.

I've seen the same thing in very low light tanks - when the minimal supply of CO2 stops things take turns for the worst within 2-3 days.

What is interesting is that even if you restore the CO2 after being off for a few days the plants hold a grudge and do not recover. I guess what happens is that there is a long adaptation period to the low or short period light and you cannot just change things the way you feel you can.

Moral of the story: There is something to be said about timelines for this hobby. How long should one expect things to settle and start to run normal. For most folk things should start on Day 1 (look at posts asking about CO2 and ferts the day after setup). Luis Navarro told me once that he thinks that a tank establishes only after several weeks - at least 6, 8 is better, some take longer. What he meant by "establish" I do not exactly know. But if we talk about deficiencies we should also consider the question "when is all that is happening happening"?

 

[Yo-han]

I find this most interesting Zapins! Lets turn it around. Lets take a high light (200 PAR at the substrate) tank like mine. We supply everything there is but no extra CO2 except what bacteria and fish produce. What would happen? Can you (or anyone) keep this tank algae free without CO2? I would love it if the answer is yes, but I doubt it can be done without limiting growth somewhere else. IME CO2 as a limiting factor in plant growth is asking for an algae infested tank, unless light is low. Limit PO4 or K and suddenly without CO2 it is possible. So for me a CO2 deficiency is more when it is limiting growth, nothing else but CO2. I firmly believe this will always show up as a deficiency, easiest notable in the form of algae. But I really want to be wrong on this one But any high light non CO2 tank I've tested was limited in PO4 or K, or NO3 or PAR was way lower than expected for that wpg. (or was algae infested and a CO2 kit solved all problems).

 

[Tugg]

Since algae are typically viewed as a parasite/diseases, then in a high light example with CO2 being the only limiting factor it has developed into a deficiency.

The lack of CO2 is causing harm to the plant, and the setup isn't sustainable. An adjustment needs to be made.

 

[Zapins]

See that is exactly what I am talking about. There are some very large misconceptions in the hobby that have come about over the years and I believe they are interfering with our understanding of what is actually occurring in our tanks. Algae is not a disease, nor has it been proven to occur only when the plants are doing poorly.

Algae is a completely separate organism that has no direct relation to plants at all. Your argument is the same as saying "since many people consider snails a disease/parasite in planted tanks then their presence means the plants are deficient."

I am curious, doesn't a deficiency imply harm is being done? If someone is on a diet and they eat a little less to lose weight are they now suddenly anorexic? Anorexia is a food deficiency that causes horrible disease like conditions in the body, eating a little less does not cause the same problems. That is the difference I am referring to with CO2 Deficiency and CO2 limitation.

See my first post:

To me, the most meaningful definition of deficiency implies the plant is harmed by the lack of a particular nutrient. A deficiency causes a disease like state that leads to injury, damage or death. If nothing bad happens then it is not a deficiency.

Having less CO2 slows growth but growth is still perfectly healthy and the plant will still grow to the same size and shape as those in CO2 supplemented conditions, therefore it is not deficiency but rather a speed of growth regulator. I believe a CO2 deficiency can indeed occur and would present as the plant completely stopping all new growth and dying. Since true CO2 deficiencies are difficult to make happen, even in a lab, there are few papers describing the symptoms of an acute deficiency.

 

[Phil Edwards]

If a person whose metabolism uses 1800 kcal/day only takes in 1400 kcal/day, then yes, their diet is deficient and the body has to start utilizing stored energy to make up for the lack. It just happens that some nutritional deficiencies take longer than others to show acute negative symptoms.

Anorexia is a mental disorder in which the sufferer believes he/she is chronically overweight and takes drastic measures to rectify the perceived issue; often to the point of starvation. It's different than plants not having a supply of a nutrient or nutrients large enough to meet their metabolic needs.

Consider a plant that receives insufficient carbon to supply it's metabolic needs. New growth is stunted and spindly and old growth dies because the plant is destroying old tissue to provide carbon to new tissue. That's why plants go chlorotic; they're breaking down chlorophyll to get at the N, Mg, and other components it needs to produce chlorophyll in new tissues. The plant is still alive and growing, it's just having to use up stores of materials to subsidize the needs of new growth.

It's pretty simple really, either the supply of something is deficient, just enough, or excessive.

Thinking about the idea of algae being a disease, it seems to me that the analogy is more accurate than not. Consider any number of common pathogens. When we're healthy our immune system is able to keep them at bay even though we're constantly exposed to, or are carriers of, the pathogen. Algal spores/cysts are similar to those pathogens. When the tank is healthy and the plants are doing well algae tend not to proliferate too much. As soon as things start getting out of balance (akin to stress, poor diet, lack of sleep, etc in a human) we see increased proliferation of algae. Rarely do healthy humans who receive a balanced diet and who get good sleep get sick under normal circumstances. It's the same thing with our tanks really. Algae are a symptom of an imbalance in our tanks; be it excessive light, insufficient nutrients to meet light-driven metabolic needs, or some other imbalance.

 

[Tugg]

By definition, most algae should be considered a parasite.

A parasite is an organism that lives on or in a host and gets its food from or at the expense of its host.

Parasitism is a non-mutual relationship between organisms where one organism, the parasite, benefits at the expense of the other, the host…

Unlike predators, parasites are generally much smaller than their host; both are special cases of consumer-resource interactions. Parasites show a high degree of specialization, and reproduce at a faster rate than their hosts…

Parasites reduce host biological fitness by general or specialized pathology, such as parasitic castration and impairment of secondary sex characteristics, to the modification of host behaviour. Parasites increase their fitness by exploiting hosts for resources necessary for their survival, e.g. food, water, heat, habitat, and transmission.

Algae attaches to (sometimes damaging) plants, blocks out resources such as light, and consumes other nutrients the plants would otherwise use. With algae left unchecked, it can lead to futher disease and nutrient starvation in the plants.

 

[niko]

Hm, lately I've been starting to not be so sure that the intake of anything can be clearly defined as "excessive" or "deficient". Here's why:

This is an example using physical exercise but it has to do with what we are discussing here.
I finally gathered my marbles and along with too much physical work I started to work out and eat according to everything I have learned in the past 15 years. And guess what - things are VERY different than what I expected. First off I have sustained energy all day long. I sleep better (with dreams, REM, and all the good stuff). The weights I can handle have been the highest I've ever done on major lifts (involving the entire body).

The above bragging about my wellbeing has to do with what we like to think of as a "deficiency". - I eat way less!
People noticed I "lost weight" but actually I have stayed the same, in fact gained a little. Despite my refusal to believe it I must be gaining muscle and losing fat. My pants (size 42, which fit fine a month ago) fall down if I don't hold them up with two hands, haha.

Now for the interesting part - how does that have to do with CO2 and aquariums: Apparently you can run a system in a very different way and get very good results. It is all in the way you run the tank. In the case of CO2 - how you supply it. Most likely the CO2-supplementation is not just a question of bubbles per second. We know that it also has to do with CO2 distribution all over the tank, timing, and even the size of the bubbles may have a role.

But what becomes pretty obvious if we think along the above lines is that the CO2 supplementation can be "excessive" or "deficient" depending on the condition of the tank. That condition is everything that puts the plants, microorganisms, algae, invertebrates in a mode that is different from what we think is best. For example plants do not need huge amounts of light all the time. Once you turn on the lights the plants can start "eating" almost instantly or "linger" depending on the amount of N available in the tissues. That means that algae does not have a window of opportunity to eat some food before the plants start to eat. I think I read that plants also shut down faster or slower depending on the N.

So the bottom line is - CO2 will be too little if your tank is in mode X. But it will be more than enough if it is in mode Y. With all the variables you can have all kinds of modes. And do not forget that things can change without you doing anything - so your mode X can turn into mode F and you don't even know it. What is the "right" CO2 pump rate is completely dependent on what is happening in the tank.

 

[niko]

Algae are as much of a parasite as yellow corn and dogs as pets.

Corn, which has been spread by people over vast areas of land is viewed by some people as a species that has found a symbiotic relationship with another species (humans) which allows the corn to do things to other plant species that they never dreamt about. Take over their land with the help of a more intelligent being.

Dogs with their cute, funny, protective, useful, amusing interactive personalities are also viewed by some as parasites. They trick you into taking care of them, make it hard to neuter them, and once you have them it's rare to not fall in love with them sooner or later.

All animal babies pull tricks like that too - cute faces, need for protection. Some people believe that is an evolutionary adaptation similar to parasitism. Makes you do things and help them survive, right?

And I am not convinced that Hidrilla, a horribly aggressive aquatic plant, is much uglier than some kind of amazing Eriocaulon.

It's all in the way we look at things. And in a funnier note - look at these individuals. Put aside the exceptional intelligence and the looks attractive to everybody else but me. Do you think you can see them as parasites in any way?

 

[Tugg]

If a person whose metabolism uses 1800 kcal/day only takes in 1400 kcal/day, then yes, their diet is deficient and the body has to start utilizing stored energy to make up for the lack. It just happens that some nutritional deficiencies take longer than others to show acute negative symptoms....

The problem here is that a plant's metabolic rate is mostly controlled by available photosynthesis. A tank with a nutrient rich substrate but lean water column, moderate light, and that does not have additional CO2 can be filled with healthy growing plants. The tank is sustainable, and the plants aren't required to use stores or scavenge resources. There metabolic rate is simply lower.

Now add CO2. The plants' metabolisms accelerate to take advantage of the previously limited resource. The rate will then increase until the plant reaches its maximum potential or it runs into another limiting resource. Depending on the resource, the plant can develop a deficiency. For example, if ferts and growth rate don't limit the plant, it will eventually be limited by the amount of light. Its rate will level off at the increased photosynthesis level, and no harmful effect will be apparent.

If a scavengable resource becomes the limiting factor (such as N P or K), then the plant will try to maintain the increasing rate and develop a deficiency.

This goes hand-in-hand with how some plants are high-light plants, while other are low, and some have a vast range. I high light plant has a PAR deficiency at low light levels, it can't maintain its minimal metabolic rate. Then on the opposite end, you have things like Anubias and hornwort. Both can grow and be health with a low metabolic rate; however, the anubias' rate will top-out rather quickly with the hornwort having a seemingly supernatural max growth rate given enough resources.

 

[Tugg]

Corn and fluffy animals are symbiotic. The care we provide them is returned with nutrition, entertainment, and companionship. All of which benifit our health.

Real Housewives on the otherhand, increase stress, kill our braincells, and weaken us as a species. All of which is to their financial benifit.... thus a parasite.