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kribensis12

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I'm fairly new to planted tanks, but not to the aquarium trade. I've tried many times over the years to successfully keep plants and they've died every time. Looking back it was a culmination of poor lighting, poor plant choice and overall inexperience.

That being said, I have kept an aquarium plant alive longer than ever before - 1 year. It's an amazon sword plant. I've been using a tetra branded liquid fertilizer, but from what I am hearing, I really need to do more to encourage better growth and to expand the options of plants that I am keeping.

At the same time, I've recently planted the "Top Fin Aquarium Bulbs" that you can find at a Petsmart and 5 days in they are already sprouting! I just want to make sure that I am doing everything necessary to make sure these plants have plenty of food available.

Which brings me to my problem - root tabs (etc.) are really expensive for what you get - but I'd love to do more. Is there any budget friendly plant food available, or better yet, a DIY plant food?
 

Byron

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Some of my post may be "old news," but as you say you are fairly new to planted tanks, I will try to explain so you see the whole picture.

Light is the most important factor, as the light drives photosynthesis, which is how plants "grow." Intensity has to be sufficient for the plant--and different plant species have somewhat differing requirements--and the spectrum has to include red and blue because these are essential to photosynthesis, and having green in the mix does improve things. I will assume you are OK with light.

Second are nutrients. Light drives photosynthesis, but if the 17 required nutrients are not available, plants will be unable to photosynthesize fully or at all, depending upon the nutrient balance. Too much or too little of some or all nutrients can cause problems for plants, and usually algae takes advantage. The point here is that a balance of light and nutrients is the aim, and it depends upon the plants species and number.

Nutrients occur naturally. The "hard" minerals like calcium and magnesium are usually present in the source water, though if you live in an area with very soft water these hard minerals may not be sufficient. Fish food contains pretty much all of the nutrients, and this gets to the plants when the fish excrement (organics) enters the substrate and is broken down by various types of bacteria. This breakdown of organics is also the prime source of carbon, as CO2, which is a macro-nutrient. Sometimes the nutrients from water changes and fish feeding can be sufficient, but less likely so the more plants there are, or the faster growing the plant species, or with fewer fish.

The Tetra plant fertilizer is presumably FloraPride. I can't find the complete ingredients, all it says on their website is that it contains a balance of nutrients including potassium and iron. It may be that this is supplementing your natural nutrients from the water and fish foods sufficiently. One sword plant can manage with this, but adding more plants may result in insufficient nutrients.

A better basic fertilizer would be a comprehensive one, like Seachem's Flourish Comprehensive Supplement for the Planted Aquarium. Another near-identical is Brightwell Aquatics' FlorinMulti. Both are complete supplements, and you don't use very much. These liquids get into the water and thus feed plants via their roots and leaves. Some nutrients are primarily taken up by leaves.

Substrate fertilizer tabs can benefit, depending upon the type (species) of plant. Sword plants are heavy feeders, meaning they need good nutrition, and I have found that substrate tabs definitely help them. Bulb-type plants (not sure what you have, but Aponogeton, tiger lotus, lilies, onion plant are all bulb plants) can benefit from substrate tabs as well. I use Seachem's Flourish Tabs, one next to my larger sword plants and one for each tiger lotus and Aponogeton plant. I also use liquid supplements as I have floating plants that get no benefit from substrate tabs.

Now, to making your own. Some people do this using terrestrial fertilizers. This is not recommended. Terrestrial plants have differing requirements than aquatic, and the higher level of especially nitrate and phosphate can be dangerous. It is safer to use specific aquatic plant products. These things get inside fish, and algae can be a real problem from high nitrate and phosphates.

The products I have mentioned are more expensive by comparison, but you use very little of them. The Flourish Tabs need replacing every 3-4 months, so if you were to use one for the sword and one for the bulb, replacing every 3 months, a package of 10 could last you 15 months. This is not that expensive, considering the benefits.

API also make substrate tabs but I do not recommend them. They can create quite a mess, and from what I have heard, do not seem to be as beneficial as the Flourish Tabs.

Feel free to question anything here. I've done a lot of experimenting over my 20 years with planted tanks.

Byron.
 

StevenF

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Second are nutrients. Light drives photosynthesis, but if the 17 required nutrients are not available, plants will be unable to photosynthesize fully or at all, depending upon the nutrient balance. Too much or too little of some or all nutrients can cause problems for plants, and usually algae takes advantage.
Tetra FloraPride fertilizer from their site Q&A says it has:
Soluble Potash (K2O) - 3.00%, Iron(Fe) - 0.19%, it is derived from sulfate of potash and iron chloride. BREX
Based on my experience there is a 99% chance that you will eventually develop a nutrient imbalance with this fertilizer. I would recommend the Seachem Flourish Comprehensive. buy the smallest bottle you can find. Once opened it will eventually go bad due to microbial growth in the bottle. So once you get it put what you need in a small pill bottle and then freeze the rest.
 

NickAu

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. This breakdown of organics is also the prime source of carbon, as CO2, which is a macro-nutrient.
If you run a air stone or an air powered sponge filter, wouldn't you also be introducing CO2 and nitrogen into your tank along with the air thats being pumped in? dry air contains 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.04% carbon dioxide, and small amounts of other gases.
 

Byron

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If you run a air stone or an air powered sponge filter, wouldn't you also be introducing CO2 and nitrogen into your tank along with the air thats being pumped in? dry air contains 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.04% carbon dioxide, and small amounts of other gases.
This is a debatable point on which the "sources of knowledge" do not completely agree. But your numbers here rather disprove the effectiveness anyway. As I understand it, the gas exchange of oxygen and CO2 will be from highest to lowest, i.e., disturbing the surface will force oxygen into the water and CO2 out. Some sources do suggest the exchange is not this lopsided, but no one has yet (to my knowledge) provided any reliable evidence of this, so it is surmise. I delved into this topic on one of the plant forums a couple years ago.

I do know from my own tanks that some surface disturbance definitely increases the oxygen level in the water [I'll come back to this below]. I can't measure CO2, other than by the plants' response [sometimes the fish too], but I am certain that there is a fair amount of CO2 occurring naturally in the tanks. The "siesta" approach to tank lighting [something I do not endorse for reasons of fish health, but I mention it as relevant] is meant to provide a period mid-day for the CO2 to rebuild. This however is not really needed in natural or low-tech method planted tanks because the lower lighting and nutrient supplementation is geared to a lower balance of all of this (including CO2 of course).

I worked back to a light period of 8 hours, after which CO2 seemed to be diminished to the extent that algae had the advantage, and in one tank where the lighting is a tad more intense because the tank is shallower I had to go down to 7 hours. I have no algae issues provided I stay with this duration. In the summer, with additional daylight (brightness and duration) entering through the windows, algae re-surfaced, but once I twigged on to it, I've eliminated this in subsequent years by having the windows heavily covered during the summer months (something easy to do in a fish room). All this tends to support the theory that CO2, which is the one and sole factor I do not supplement, is the mitigating factor to photosynthesis.

The breakdown of organics primarily in the substrate is the primary source of CO2. That released by respiration of fish and plants is much less. Another proof of this I have is the reduction of oxygen and simultaneous increase of CO2 during darkness when photosynthesis has ceased. This was the reason I increased the surface disturbance in my larger planted tanks; I clearly saw the effect in the behaviour of the fish. The corys which very rarely surface for air were doing so in the early morning and quite a lot, but since I increased the surface movement, this completely stopped. That is pretty clear.

The nitrogen I don't know about, but I would suspect this isn't occurring. One of my tanks is a 20g QT for new fish. This tank is fairly well planted, and it can sit empty of fish for months. I have always observed a weakening of the plants during these periods, but as soon as fish are introduced, the plants respond positively. Now, it could be argued that CO2 is also involved, and it may well be. But given that most aquatic plants prefer ammonia/ammonium as their source of nitrogen, it would be likely that this is the answer. There is also the issue of nitrogen gas that is produced by the de-nitrification of nitrate, and this leaves the water and enters the air, at least according to every source I have read. So I accept all this.

Byron.
 
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kribensis12

kribensis12

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Wading through all of this science has reaffirmed my calling to teach History ! =)

So, from what I understand, my lighting is probably OK considering I haven't killed the sword yet. I should definitely purchase root tabs to assist my sword and possibly the bulb plants. I should also consider purchasing flourish as it is a more complete and balanced fertilizer.

Am I missing much?
 

StevenF

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As I understand it, the gas exchange of oxygen and CO2 will be from highest to lowest, i.e., disturbing the surface will force oxygen into the water and CO2 out.
The solubility of gases in water depends on the chemical reactivity of the gas, the temperature of the water and other factors. However for nitrogen, oxygen and argon these gases are barely soluble in water meaning they go into the water and then come out quickly.

However for chemically reactive gases CO2, NH3, NO2, N02,SO2 they tend to stay in water longer. As a result they will be found in water at much higher ppm levels than oxygen, nitrogen, and argon. Furthermore these reactive gases will react with excess minerals in the water potentially forming compounds such as calcium carbonate, calcium nitrate, magnesium sulfate and others.. These compounds are often solids when the water is evaporated away.

So if you bubble air into the pure water, CO2, NH3, NO2, N02,SO2would show up at concentrations much higher than the concentrations in air. As a result these gases will have a strong effect on PH while O2, N2, Ar will have a minimal affect.

I personally let the water from my filter spray bare drop down through a 1/2" of air to the water surface. I believe this will keep all the gases listed above at constant levels the water. I could do that with a air stone and pump but I don't like the sound of air pumps. Letting the water fall through air instead sounds like a fountain which I find more pleasant. With good lighting and properly fertilized water my Anacharis and Baby's tears right now are pearling (oxygen bubbles sticking to the leaves). Most people only see this in tanks with CO2 injection, which I don't have.

In my mind over aerating the water is better than slightly disturbing the surface. Test are available for measuring gases in water but they are expensive and often difficult to do without getting erroneous readings.

So, from what I understand, my lighting is probably OK considering I haven't killed the sword yet. I should definitely purchase root tabs to assist my sword and possibly the bulb plants. I should also consider purchasing flourish as it is a more complete and balanced fertilizer.
.

Correct but I would consider the root tabs are optional. I have never used them. Also note that most aquarium fertilizers on the market are incomplete. some like your tetra product and API leaf zone only have 2 nutrients. many others lack calcium, and one or more trace nutrients. Some are actually better at feeding algae than plants due to the deficiencies.

https://en.wikipedia.org/wiki/Plant_nutrition

While Seachem's Flourish Comprehensive and Brightwell Aquatics' FlorinMulti (which I didn't know about until today) are good they are not perfect. Most tanks will do fine with them but sometimes a tank will have plants with higher nutrient requirements than the fertilizer can supply. I recently found in my tank that Flourish wasn't providing enough sulfur to satisfy my plants.
 
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NickAu

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Thank you Byron and Steven,

I personally let the water from my filter spray bare drop down through a 1/2" of air to the water surface.
I do it this way on my Betta tanks
 

Byron

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Steven has explained the exchange better than I can (thanks). When I used "surface disturbance" earlier I was actually meaning something closer to what Steven and Nick have both mentioned. In my 70g, which is fairly heavily planted (photo below) the spray bar on the left is positioned such that the return water hits the glass just above the surface. This sometimes causes very tiny bubbles in the tank water around the spray bar, but it also ripples the water more. This was the tank with the oxygen/CO2 issue I wrote of, and this solution solved that. This is also the tank that seems to run out of CO2 faster than the other seven, as the light is slightly more intense with the shallower depth.

A bit more on liquid fertilizer and substrate tabs. This is something I have gone into more because of a specific organics issue in the 90g (less in the 70g). To cut to the findings...I have very soft water (near-zero GH/KH) so the only minerals are those I add via fish foods and plant additives. Obviously I have a lack of "hard minerals" (calcium and magnesium primarily here) with such soft water. Due to the organics and algae issue I eliminated all liquid additives (I had been dosing Flourish Comprehensive and Flourish Trace). I used only Flourish Tabs next to the larger swords; Seachem says the nutrients do not leech into the water column as occurs with liquid fertilizers, and my findings seem to confirm this. The plants had been showing definite symptoms of calcium deficiency after I stopped the Equilibrium [this is a "hard" mineral additive] and Flourish Comprehensive supplements, but within a very few weeks with just the tabs (replaced every 2 months instead of the suggested 3-4) these symptoms completely disappeared in the newer leaves. The algae disappeared. It has now been almost two years since I last used Equilibrium, and as you can see from the photo there is no calcium deficiency. Flourish Tabs have a fairly complete span of nutrients, comparable to the Flourish Comprehensive liquid.

Over the years I have used just the liquid, both liquid and tabs, and just tabs, for several months each. The liquid on its own works, the tabs alone work (but only on substrate-rooted plants), and both together work. I found the most obvious difference was when I added the tabs with the liquid. For plants like the larger swords, they simply exploded. I have a single sword plant (Echinodorus grisebachii, the "bleherae" form) in the 90g, and with just the tabs for some six months, it presently has seven inflorescences with adventitious plants. I see some signs of calcium deficiency in the adventitious plants which are not root in the substrate, and a month ago commenced using Flourish Comprehensive at half dose. That tank has the organics issue which seems now to be under control, so I have been careful with plant additives.

Byron.
 

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kribensis12

kribensis12

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I've been doing some research and I think I will do both the flourish tabs and the flourish liquid.

Looking at my sword, I am seeing some yellowing on the leaves and the leaves seem to be thinner/more narrow. From what I've read that is usually due to a deficiency of minerals such as iron. I'll try this combo and see if it provides more of what my plants need. I'd love to see the sword really take off! For the most part it has been fairly homeostatic - just maintains itself, but does not really thrive.
 

Byron

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I've been doing some research and I think I will do both the flourish tabs and the flourish liquid.

Looking at my sword, I am seeing some yellowing on the leaves and the leaves seem to be thinner/more narrow. From what I've read that is usually due to a deficiency of minerals such as iron. I'll try this combo and see if it provides more of what my plants need. I'd love to see the sword really take off! For the most part it has been fairly homeostatic - just maintains itself, but does not really thrive.
Diagnosing plant issues is not at all easy, as there are similar and identical symptoms for different problems, including light and nutrients. Also, if you mean the new growth is more yellowish (new leaves on swords arise from the centre of the crown, with the oldest leaves on the outside) that is one thing, but if you mean the older leaves are yellowing, that is quite another. Yellowing leaves occur with several deficiencies including light; chlorosis (the term for yellowing of leaf tissue) is a lack of chlorophyll, but a plant may be hindered from producing adequate chlorophyll from a deficiency of several different nutrients, as well as light intensity. There are several nutrients needed for the stages of chlorophyll production.

Calcium deficiency usually begins as brown blotches on leaves that keep enlarging until the entire leaf yellows and dies; but the brown spots are in fact iron deposits, which the plant is taking up to replace the calcium. So one might think there is an excess of iron, when it is actually a calcium deficiency.

Iron is frequently suggested for yellowing leaves, and it may sometimes be the insufficient nutrient. But as an example, if you then start adding iron, the plant may reach the point where it cannot take up any excess and it can then begin shutting down assimilation of certain other nutrients. Both Flourish Tabs and Flourish Comprehensive Supplement include iron, and in almost all cases it will be sufficient. The low-tech or natural planted tank approach which is what we are talking about here does not usually involve plants that have excessive nutrient requirements, as the light and CO2 will not be sufficient for these plants. That does not mean some nutrient may still be lacking.

But there is another aspect of nutrients to keep in mind, and that is that plants need them in rather specific proportions to each other. Some nutrients if in excess can be detrimental since the plant may stop taking up certain other nutrients, as I mentioned above. How this occurs is that the plants will take up the excess nutrient to store, but the nutrient may compete with certain other nutrients, preventing their uptake. And all plants' ability to store nutrients is limited to some extent depending upon species.

The liquid fertilizer will benefit all plants, whether substrate rooted or floating or rooted on wood/rock, because the nutrients are in the water column and plants can only take up nutrients from the water (aside from the nutrients like CO2 which can come from air if leaves are floating or above water), via roots and leaves. You will see an improvement with a tab for the sword. Provided the light is not an issue, which from what you've posted so far wouldn't seem to be.

Byron.
 
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