Proper Way to Fertilized Aquarium Plants

[dwencel24]

Hi everyone,

I have been into aquarium plants for quite some time now. I have been successful in growing plants by research and trial & error. After getting into aquarium plants, I decided to try fertilizer. Before starting, I was in a dilemma because I have dwarf crayfishes, kuhli loaches, and snails (assassin and netrile). So, I tried to apply my engineering background to properly fertilize my plants without poisoning my fishes.

Most of aquarists just dump fertilizer into their aquarium. Majority of them are successful in growing plants. I will say this is wrong (dumping), and this is scary (growing plants). I said that JUST dumping fertilizer is wrong because the fertilizer are being wasted. First, assuming that the aquarium is cycling properly (which means ALL the aquarium water is being run through the filter), the fertilizer are being absorb/adsorb by the filter. Probably, only 5-10% of the fertilizer are being use by the plants. This make sense if the snails and others that are sensitive to fertilizer are still alive.

"Wait, can you explain then why my aquarium plants are propagating?" I said this is scary because it means that the aquarium water is not properly cycling. Water test for pH, ammonia, nitrate and nitrite may show great results. But is that true for EVERY part and/or side of the aquarium? Probably not. This means that the fertilizer contents (depending on molecular weight, solubility, diffusion, etc) will likely stay on the area it was dumped. This is highly true for large and cycled (long-been stablished) aquariums. This could also mean that the plants are highly relying on debris and fish food that are not being suck out from the aquarium as fertilizer.

I have done and been doing direct-root injection to my plants. The result is astonishing!! They are propagating crazy (which they are suppose to be). I used to have problems with algae that even my algae-eaters could not solved, which this technique have solved. Some may argue that soon enough the fertilizer will come out to the water. Indeed, this is true. However, if the dosage is small, this won't likely happen. In addition, I have sand as my substrate. This means that the fertilizer will have slower diffusion out from the sand. As for my rock/wood rooted plants, I put sponge and/or coconut coir on their roots. These will serve as fertilizer-holder. Very small amount of dosage will make sure ALL the fertilizer contents will be absorb before they can even diffuse (absorption rate >> diffusion rate).

That's it!! Any comments, opinions, and suggestions are appreciated.

 

[Fresh2o]

What kind of fertilizers are you using and how often are they being added?
What kind of lighting are you using?

 

[dwencel24]

Fertilizer: Flourish
Dosing: Every week after 25% water change
Lighting: Two 10 watt fluorescent bulbs

 

[Fresh2o]

That appears to a low light setup (depending on the tank height) and suitable for your fert regiment. It may not work in high light setups. The nutrient and CO2 demand is quite high.
I dose daily directly to the water column using a modified PPS-Pro setup. Weekly 30-40% WCs. Substrate fertilizers added every few months. Algae not an issue aside from some BBA on the rocks.
Not sure what you mean about the filter absorbing nutrients. How so? By using activated carbon or some type of resin?

 

[dwencel24]

I tended to go to low light setting since the aquarium is not placed in a dark place (to save energy). There's no point in using high lighting in my case since I have kuhli loaches and cory catfishes.

In addition, I don't use CO2 because it's not really soluble in water depending on temperature (waste of money). To keep a lot of CO2 under water, the container must be pressurized (like carbonated water and soda). Also, CO2 will replace other gasses like oxygen. But this is not a problem since the plants are producing 6 oxygen for every 6 CO2. It might be a problem at night though. Water cycle that inserts oxygen by filtration also inserts other gasses like CO2 from the atmosphere.

Activated carbon filters debris and other organic junks. They are not good in filtering minerals and salts. My apologies if I used the wrong terms (adsorb/absorb). Although that was the case, this means that the fertilizer contents are cycling around the aquarium and barely use by the plants. Plants have less chance to absorb a nutrient particle (plant absorption rate << water transport rate) unless the water is nutrients saturated. True, that most are staying in the aquarium because of small water change. However, still, most of the nutrients are being wasted by water change. In addition, nutrient accumulation in the filter (depending on what you have) is quite possible, which again prevents plants to absorb them.

 

[Fresh2o]

My shrimp tanks are low light no ferts. Shrimp are the focus and the plants are secondary.
Oh, I know about gassing fish. Lost a school of Furcata Rainbows a few years back because the CO2 was running a lot higher than it should have been.

 

[Bert2oo1]

Yea good info here and a great idea for a low tech approach. I agree with fresh, in a high tech environment it wouldn't work due to the demand of co2 and ferts required by the plants.

The same approach you have made can also be done with roots tabs. If you know abit about ferts I'm sure you could make up some DIY tabs that cover all bases.

Co2 is certainly not a waste of money and if you ask me once you've used it you would never go back to non co2 injection. If your equipment is set up properly and you know what your doing it's hard to gas your fish.

What types of plants are you growing with this method? Also do you have any pictures you can share?

 

[dwencel24]

I actually have thought about using root tabs. However, it is very hard to control the dosing with solids. In addition, root tabs are expensive and very saturated, which again can cause leakage/diffusion out from the substrate (waste) – diffusion rate to the water is definitely higher than absorption rate to the plant.

I just don't believe much in CO2 supplementation. I have seen lots of solubility tables and graphs of oxygen and CO2 while in college. Unless the temperature is below room temp and the water is isolated (no atmospheric contact), the water will not hold gasses as assumed for.

There are ways to get CO2 without buying supplements. One way is to increase surface area of water inflow to the aquarium. Another option is to use air pump with very fine air stone. Small air bubbles mean large surface area. These options will increase water-air contact for more CO2 and oxygen in the water. These will also provide non-stop CO2 injection to the aquarium.

I have dwarf lily, anubias, and java fern, water snowball. I will be taking and posting some pics in the morning.

 

[Bert2oo1]

I actually have thought about using root tabs. However, it is very hard to control the dosing with solids. In addition, root tabs are expensive and very saturated, which again can cause leakage/diffusion out from the substrate (waste) – diffusion rate to the water is definitely higher than absorption rate to the plant.

I just don't believe much in CO2 supplementation. I have seen lots of solubility tables and graphs of oxygen and CO2 while in college. Unless the temperature is below room temp and the water is isolated (no atmospheric contact), the water will not hold gasses as assumed for.

There are ways to get CO2 without buying supplements. One way is to increase surface area of water inflow to the aquarium. Another option is to use air pump with very fine air stone. Small air bubbles mean large surface area. These options will increase water-air contact for more CO2 and oxygen in the water. These will also provide non-stop CO2 injection to the aquarium.

I have dwarf lily, anubias, and java fern, water snowball. I will be taking and posting some pics in the morning.

I agree with what your saying but this certainly isn't the case for all aquatic plants, the plants you currently have are classified as easy growing plants and can grow in most conditions.
Not saying your technique isn't good because i completely understand that it would work perfectly with the plants and setup you have.
But Plants like rotala, bylxa japonica, Monte Carlo, HC Cuba, pogostemon helfari, ar mini, etc etc wouldn't work with this technique due to the lack of co2 and lighting. To maintain a high light aquarium with high light requirement plants you must have 25-30ppm of co2 in the water column for the plants to use in photosynthesis. If that co2 level is not maintained algae comes into play as the plants decay and it end up in a hell of a mess.

I'm a big believer of having ferts both in the substrate and in the water column for plants to thrive. I have topsoil in one tank and Ada soil in another to provide nutrients plus I dose the water column to make sure nutrients are readily available at all times.

 

[Fresh2o]

I agree with the above post. I would not have had much success with my tanks without an ample CO2 and fert supply. I agree that only so much CO2 can stay in solution...that is why it is injected in the water column via a fine diffuser or pumped into a reactor.
In high light setups, Liebig's law of minimum is being applied to the amount CO2 and fertilizers added. Insufficient quantities of either will be the limiting factor for plant growth. When deficiencies occur, plants can go downhill quickly. Opportunistic algae often appear to further complicate things. Basically, the tank is being flooded with both and yes, care must be taken if livestock are present.
As for saving costs, DIY root capsules is a popular option. This is basically Osmocote 2 packed in clear capsules. I use AquFertz root pellets from AquariumPlants dot com. Not bad at 75 pellets for ~$10. I only add 6-10 every 3-4 months. The PPS-Pro kit I bought in 2013 cost between $20-30 and I have quite a bit of it remaining. My CO2 cost for refills is about $15-20 annually.

 

[toolman]

I really have to agree with Bert2oo1 & Fresh 2o my tank would not be where it was without daily dosing of pps-pro ferts. I used no ferts for about a year and my plants were growing realllly slow, buy looked OK. When I started the pps-pro ferts the difference was astonishing, I got a finnex 24/7 planted + light and was working my way to med-high tech with the intention of getting co2 fairly soon because excel just wasn't cutting it anymore keeping the algae away. I don't have a lot of algae buy it is there ready to take over if given the opportunity.

I did not get the opportunity to do that because my 75 developed a tiny leak and I had to tear it down this past weekend in preparation for resealing. I have learned a lot from both of these guys posts (and Caliban, Ashenwelt, and many others on the forum) and when I get it back up and going will take the next leap in planted tanks from my current low tech to high tech. I truly believe there is a lot of truth to what you are saying, bit the high tech/high light tank requires the column ferts, root ferts, and co2 to be a success.

I do believe your right though, Low tech/light with precision placement of ferts and no co2 can have good results, but with more demanding plants they're spot on.

 

[Funken_A]

Hi everyone,

I have been into aquarium plants for quite some time now. I have been successful in growing plants by research and trial & error. After getting into aquarium plants, I decided to try fertilizer. Before starting, I was in a dilemma because I have dwarf crayfishes, kuhli loaches, and snails (assassin and netrile). So, I tried to apply my engineering background to properly fertilize my plants without poisoning my fishes.

Most of aquarists just dump fertilizer into their aquarium. Majority of them are successful in growing plants. I will say this is wrong (dumping), and this is scary (growing plants). I said that JUST dumping fertilizer is wrong because the fertilizer are being wasted. First, assuming that the aquarium is cycling properly (which means ALL the aquarium water is being run through the filter), the fertilizer are being absorb/adsorb by the filter. Probably, only 5-10% of the fertilizer are being use by the plants. This make sense if the snails and others that are sensitive to fertilizer are still alive.

"Wait, can you explain then why my aquarium plants are propagating?" I said this is scary because it means that the aquarium water is not properly cycling. Water test for pH, ammonia, nitrate and nitrite may show great results. But is that true for EVERY part and/or side of the aquarium? Probably not. This means that the fertilizer contents (depending on molecular weight, solubility, diffusion, etc) will likely stay on the area it was dumped. This is highly true for large and cycled (long-been stablished) aquariums. This could also mean that the plants are highly relying on debris and fish food that are not being suck out from the aquarium as fertilizer.

I have done and been doing direct-root injection to my plants. The result is astonishing!! They are propagating crazy (which they are suppose to be). I used to have problems with algae that even my algae-eaters could not solved, which this technique have solved. Some may argue that soon enough the fertilizer will come out to the water. Indeed, this is true. However, if the dosage is small, this won't likely happen. In addition, I have sand as my substrate. This means that the fertilizer will have slower diffusion out from the sand. As for my rock/wood rooted plants, I put sponge and/or coconut coir on their roots. These will serve as fertilizer-holder. Very small amount of dosage will make sure ALL the fertilizer contents will be absorb before they can even diffuse (absorption rate >> diffusion rate).

That's it!! Any comments, opinions, and suggestions are appreciated.

EI fertilization is a waste how ???. I buy bulk powders and mix in a certain amount every single day. At weeks end I have a build up so I do a water change. That water works wonders in my container plants. Nothing wasted . What filtration are you using that removes fertilizers. Carbon filters are big NO NO in a planted tank, they are known ot remove trace minerals. I use filter floss bioballs sponge and perlite, which one of these filtrations absorbs dissolved ferts ???? Bio Wheels also degas CO2 from the water column and are not recommended in a planted aquarium. I don't use any filtration that would remove fertilizers in my aquarium. Where did you get the only 5 to 10% ferts being absorbed by plants. How do you know this and how did you come to this conclusion???? Why do you think people are poisoning their fishes ? You do realize that natural streams and rivers are loaded with all kinds of "fertilizers". In cases of pollution where run off has increased nitrates/phosphates to an unhealthy levels you will see dead fish everywhere, but we are no wheres near these levels in planted aquarium unless someone is completely uneducated and careless


CO2 is completely necessary for plant growth. In low light situations there is enough CO2 equalized in the water and plants are not demanding more CO2. With higher light not injecting CO2 is guaranteed algae.
Saying CO2 is a waste is kind of funny. I can turn off my CO2 today and by tomorrow I will have issues and by weeks end I will have a mess. If CO2 is a waste then why would that happen. You do realize CO2 dissolves into water., We are not trying to create a carbonated beverage, we are trying to achieve 30ppm + consistently during light on period. In fact Carbonate hardness is directly cooperated to the amount of CO2 the water column can hold. You are mis informed on CO2 in water IMO

As for aquarium plants many stem plants feed through the water column more so than the roots.. Not all plants do well with substrate only fertilizing. Many are propagated from streams with fast moving waters and grab their nutrients via leaf


I follow the teaching of Tom Barr. This is man with multiple degrees and decades of experience who has penned many tutorials, dissertations/papers, and has done plenty of talks to hobbyists around the world. He owns aquarium businesses and is quite successful consultant...From him I have perfected for my aquarium an EI Fertilization schedule, CO2 injection, and liquid CO2 addition.
I actually had used fertilizers very sparingly early on and had algae issues. I upped my ferts considerably and have great growth, and have never looked back. Algae subsided plants look fantastic.


If you are convinced that you have a new way of doing things. You need to set up a tank with lots of high light requirement plants do not inject CO2 and only do you substrate fert method.. DO a journal and see what happens. if you are successful you can write a book and some papers and start a business

Maybe you got this figured out, but to pretty much call out massive research done by very dedicated hobbyists who have spent decades perfecting what we see today is bold.

 

[fishenthusiast]

To recall from my general chemistry days in college, carbon dioxide is nonpolar and water is polar. This doesn't mean that CO2 will not dissolve in a high enough quantity for a planted tank with pressurized CO2 (as Fresh mentions, that is why we people use a reactor or a diffuser), as CO2 will actually dissolve well in water due to the interactions between the two molecules given the right conditions (as previously mentioned). Water can be a nucleophile or an electrophile. When water reacts with carbon dioxide, water acts as the nucleophile and CO2 acts as the electrophile (the two oxygen atoms remove electron density from the carbon atom). The d- (partial negative charge) oxygen in H2O will "attack" the electron deficient carbon in CO2 and cause an intramolecular reaction to form carbonic acid in an equilibrium. Remember that we are measuring the amount of CO2 in ppm, which is rather small, but it makes a huge difference for plant growth biologically. CO2 is important as it builds up plant biomass, and with light, will produce oxygen.

In terms of EI, I'm not a huge fan it, but it works for many. As long as the plants are getting their nutrients, and proper water changes are done to prevent accumulation of excess nutrients, then the tank should be healthy.

 

[Caliban07]

Plants don't need 30ppm of co2, even in a high light tank. It's very much species dependent but in most cases doubling atmospheric equilibrium levels has shown to increase yield in many species. 30ppm helps but it is by no means necessary. Plants will grow more slowly in lower levels.

It's very important to remember that EI is also unnecessary. If you go by the work of Marcel Golias in his webpage (may need translation) https://www.golias.net/akvaristika/experimenty-spotreba-zivin he shows that even in high PAR, densely planted aquaria that weekly nutrient uptake is pretty low although uptake was higher at higher concentrations.

I haven't seen any kind of studies undertaken or any scientific papers that support the idea of Estimative index. In fact the only paper that the EI method was derived from actually mentions the possibility of toxicity from relatively high micro nutrients.

Not that EI doesn't work as it clearly does in some cases but it is definitely not the silver bullet when it comes to nutrient dosing.

Every tank is different and it is better to have an open mind when it comes to growing plants. That way it's easier to understand that there are many different ways to successfully run a planted tank.

 

[dwencel24]

I guess that I was misinterpreted . I never said don't use fertilizer. In fact, I do use it too. Nutrients in fertilizer are also necessary for plants’ photosynthesis. I do know that there are natural fertilizers in nature's flowing waters. The difference is that fertilizer is constantly flowing from decaying matters and other natural sources. Rivers and oceans also have mid to high water turnover, which allows proper water circulation for proper nutrients and CO2 flow for plants . In addition, rivers and oceans have large surface area that helps in maintaining CO2 in water, which aquariums don’t have. This was the reason that I suggested air pumps and inflow agitation. As for CO2-water equilibrium, only 1% of CO2 converts as carbonic acid and 99% are dissolved gas . In addition, CO2 is indeed not very soluble in water. Say you inject 30 ppm in the water. That 30 ppm of CO2 will not be the same over time. Not just because plants absorb them, but also most of it has surface out from the water (depending on temp, of course) . Therefore, CO2 must constantly introduce (like water flow) in the aquarium for plants . SIDE NOTE: High CO2 partial pressure in the atmosphere due to excessive combustion has increased CO2-water solubility. Now there are too much CO2 in the ocean, which are killing coral reefs (too acidic).

I never said CO2 is not necessary for plants (that's just crazy) . I was saying that the CO2 supplementation is not. I am completely aware of photosynthesis/respiration (6CO2 + 6H2O <--light--> C6H12O2 + 6O2). According to Le Chatelier's principle, respiration will occur if there is low amount of CO2. So, CO2 is necessary for aquarium plants to thrive. Now, my point is that you can get CO2 without purchasing CO2 gas (as I have mentioned how). In aquarium setting, plants have plenty source of hydrogen and oxygen (water), but not carbon, which is one of the backbones of plants. There are two natural sources of CO2: (1) the creatures that breath in your aquarium, (2) the atmosphere. In aquarium setting, these are not vast though. Furthermore, there is plenty source of carbon not just CO2. SIDE NOTE: Liquid CO2 is nonsense since liquid CO2 does not exist in atmospheric pressure (look at CO2 T&P chart/graph) . These supplementations have, however, different kind of organic matters that are derivative of CO2. But plants are picky to how they absorb carbon and what source they can take without necessary conversion of organic matter to CO2.

Plants are like chemical reactor plants. CO2 and water are the reactants, glucose and oxygen are the products, and enzymes in plants are the catalyst. It is an endothermic reaction (by light though, not heat). In a high-light setting, there is plenty source of energy (light). But without CO2, plants cannot do anything. Furthermore, the only difference between high and low setting plants is that one is slow-absorbing and the other is fast-absorbing. Slow absorbing plants require high-tech settings because you should constantly provide reactants and energy for the reaction to occur. However, most of the reactants and energy will not be absorbed, which is just nature of most reactions (waste -> thermodynamics).

Just for the record, I have nothing against using any of these . Like I said, I, myself, use fertilizer. If things are working well for you, then it’s all good . I posted this to give other people options (cheaper and natural way) in starting on their aquarium plants (easy-moderate-hard). These information that I shared were from my college years of engineering/science experiences and reading scientific published journals . My apologies if I was misinterpreted.

 

[Caliban07]

I didn't misinterpret [emoji846]. No disrespect to Funken but I think Tom Barr has created a bit of a monster in the sense that most who follow his methods are usually confirmation bias even though they have no idea why the beliefs they follow work or where the beliefs came from (not aimed at anyone here) but I've seen it. I was it at some stage in the hobby. I'm not saying I know any better than anyone else only that I find more solace in the quest for deeper understanding.

Welcome to the forum.

 

[fishenthusiast]

I will note that there was a member who ran a high light tank without pressurized CO2 years ago. Check out: http://www.aquariumadvice.com/january-2013-totm-rivercats-220-gallon-planted-community/. She was using glut as an additive though. I run pressurized CO2 in my low light tank. Do I need it to have a successful and lush scape? In my case, no. Since I have no other tanks, I put the $300 system to use! It'd do no good to have it sitting in the closet haha. Do I think it helps? Yeah, a little bit. When you get in those higher PAR ranges, that's when pressurized CO2 almost becomes a necessity. Via a diffuser, a lot of the CO2 will end up gassing off. With a reactor, most of the CO2 will dissolve within the chamber if the bubble count isn't too high and the flow isn't too high (less contact time between water and CO2). With a reactor, you have to be really careful about gassing your fish.

In terms of fertilization, my take on EI is that in the end, it doesn't really help that much. I used EI for a month and I noticed no difference in plant health or growth (note: that wasn't a long time to use it, but it wasn't doing my tank any favors). I've found that micros need to be dosed more than macros for my tank. I dose macros every three days, and I dose micros every day with a syringe (in low quantities). I know Tom Barr has some nice tanks, but I often find myself questioning the EI regimen. I've used PPS-Pro in a high light build and a low light build with success--I'll note that my tank has a high water hardness as well, as there is a lot of limestone deposits in my neck of the woods. By the way, and just for everyone's information, GLA changed their recommended PPS-Pro dosing from the last time I saw it. http://blog.greenleafaquariums.com/2013/02/28/our-new-pps-pro-fertilizer-pack-just-mix-dose/. Other fertilizer regimens are fine. Flourish, Tropica, etc.

That's my take on it. I think threads like this are good. It allows us to expand our knowledge and question our methods. I think the OP makes some valid points! Fishkeeping involves a ton of science, and we all know that science is an ever-evolving topic--new things come out everyday.

 

[Bert2oo1]

100% agree with all here, I hope I didn't come across as if I was pooping on your method of dosing as I'm not. I think it's a great way to fertilise a low tech tank or even medium for that matter. Having ferts available at the roots is massively beneficial to aquatic plants and it 100% works. If it didn't why would Ada and similar substrates have nutrients in there?

No one can steer me away from that 30 ppm target of co2 tho, not even caliban [emoji16][emoji23] I'm a co2 and flow preacher untill I die [emoji38]

 

[toolman]

Agree with Bert2oo1, not saying anyone is right or anyone is wrong.
Every situation is different and unique, what works for you doesn't always work for me or everyone else.

To the OP and everyone else I wish I had half the knowledge you guys have. As my name says I am a Toolman, college educated in technology, but just a simple country boy. I try every day to learn something on here and hopefully gain s better understanding of aquarium's and aquatic plants.

Different methods and discussions like this are great, really no right and wrong. Welcome any views and experiences so we can learn.