CO2 and fertilizer -- what kind should I use?

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I_Smell_Fish

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I have a 15 gallon planted tank with high output light. I use liquid CO2 that I dose everyday, which is Excel. I also use plant fertilizer twice a week, which is Excel Flourish.

1. Is liquid CO2 adequate, as opposed to injected CO2?
2. Is liquid fertilizer adequate or are the tablets better, or something else?

I have giant hair grass and some sort of rotala. The tank is new so they are growing fine at this point, but I don't want them to die.

Thank you,
Darrien
 
If you want a cheaper method of objecting CO2 a lot of users opt to use a CO2 fire extinguisher - by simply removing the horn and installing a regulator and solenoid you can have a CO2 set up at a fraction of the cost of a system aimed at the aquarist.
 
Yea I have seen those, look neat, didn't tom barr make one on the back of his truck?
 
I have a 15 gallon planted tank with high output light. I use liquid CO2 that I dose everyday, which is Excel. I also use plant fertilizer twice a week, which is Excel Flourish.

Carbon is one of many nutrients plants need. Typically CO2 is the source. However some time ago a liquid chemical was found that plants could also use as a source of carbon. Flourish Excel is one brand containing this chemical. This chemical is corrosive and will harm some plants. Plant also use water to get the hydrogen they need. They use light as an energy source. However If you put a plant in pure water with unlimited CO2 and and light. The plant will die. Water, CO2, and light isn't enough

There are a lot of minerals that plants also need. We call them Macros (plants need a lot of these) and micros 9plant need less of these. If plants are short of one of of these the plants may not grow or die. You are not using a mineral fertilizer. Without that something will always slow or stop plant growth.

This Wikipedia article lists all macro and micro nutrients.
https://en.wikipedia.org/wiki/Plant_nutrition .

I would suggest one of the two fertilizers, These fertilizers are more complete than most on the market.
  • Sachem Flourish Comprehensive. This Is not Flourish Excel! Comprehensive Coves 14 of the 15. It is short of nickel. Eve though I have very soft water my aquarium is somehow getting enough nickel. Probably from fish food. Sachem designed this fertilizer to be a little weak in macros But fish food is rich in macros so it still does well in most cases.
  • Brightwell Aquatics Florinmulti contains 13 of the needed 15 and is short nitrogen and phosphorous. Most aquariums have these in abundance. So you can ignore the deficiency and probably be OK or you can add some nitrogen or phosphorous as needed for your aquarium.
You could mix your own at probably cheeper cost but that is not necessarily easy. For someone new to fertilization I would recommend Starting with the above two for starters. If you want in the future you could adjust them to your tanks particular water conditions.

. Pressurized Co2 is about 300$ but is the right way to go.
http://nilocg.com/diy-ei-liquid-fertilizer/ fertilizer
Pressurized Co2 http://greenleafaquariums.com/products/gla-gro-co2-system.html

You have choice here you may not know about. The air you breath has 400ppm of CO2. CO2 is typically present at that concentration in your tank. In many cases it may actually be higher in water. Fish also produce CO2.

You don't need to spend a dime for a CO2 system. many people on this forum don't use CO2 and still get good plant growth. Better aeration of your aquarium water (air stone or more egressive surface agitation (water fall for example)) will insure CO2 enters your tank as fast or faster than your plants can use it. And it cost a fraction of the cost of a CO2 system. With just optimal fertilization plant growth can be quite rapid. The main reason to use CO2 is that with it you can get even faster growth than what you ca get with mineral fertilizers alone.
 
plant growth is different than plant health. Plant health contains many elements, Co2 being one of them. With an airstone you cannot control how much Co2 is being pushed into the aquarium, if at all. And its unsightly, and inefficient
 
With an airstone you cannot control how much Co2 is being pushed into the aquarium, if at all. And its unsightly, and inefficient

CO2 reacts with air to form carbonic acid. Plants use the carbonic acid. The amount of CO2 that can be resolved in water is preciecly know and it is temperature dependent.
solubility-co2-water.png


So at common aquarium temperatures (20 to 30C). Water will saturate with CO2 at 1.5g per Kg of water. If CO2 levels in water are below this the water will pull it out of the air. CO2 levels in are are 400ppm. converting 1.5g per KG equals 1500ppm.

So if you have good aeration you should be able to keep your water at 0.5g per Kg or higher. Additionally some of the CO2 dissolved in the tank reacts with with potassium, magnesium, and calcium to form carbonates which plants can also use as a CO2 source. So aquarium water will generally have more than 0.5g per Kg of CO2 because the table above doesn't include carbonates. That is a lot more carbon than most people expect.

Most users of CO2 systems use a drop checker to determine there CO2 levels. The general recommendation for CO2 is a 30ppm reading from a drop checker. A drop checker isn't saying you have 30ppm in the tank. It is actually saying you have 30ppm of CO2 above the normal level in water which at a minimum is 400ppm.

I just use my filter a water pump to aerate my water. It cost me about 3 cents a day ($1 dollar a year) in electricity costs to run it. The one time startup cost of $300 for a CO2 system plus occasional CO2 refills is much much higher.
 
It boils down the lighting, if the lighting is so intense that the plants are utilising the CO2 faster than it can dissolve in water then they will be deficient - period - which means an additional CO2 source is required.

A pressured system will always dissolve CO2 into water much faster and efficiently than running an airstone. The ongoing costs are minimal (refills are free if you know where to go) personally I prefer high energy set ups with fast plant growth - not only that but some plants will not grow without CO2 injection - which means that you aren't limited.

Healthy plant growth is achievable with or without CO2 - it just depends on what your goals are - pointless negging on either method - it's up to the OP to choose which path they'd prefer to go down.
 
You need an equal (so to speak) amount of micros and macros, flourish doesn't offer this with what your using. There is no such thing as Liquid Co2, your using Glud. Pressurized Co2 is about 300$ but is the right way to go.
http://nilocg.com/diy-ei-liquid-fertilizer/ fertilizer
Pressurized Co2 http://greenleafaquariums.com/products/gla-gro-co2-system.html

Do you have any experience or opinion on
You need an equal (so to speak) amount of micros and macros, flourish doesn't offer this with what your using. There is no such thing as Liquid Co2, your using Glud. Pressurized Co2 is about 300$ but is the right way to go.
http://nilocg.com/diy-ei-liquid-fertilizer/ fertilizer
Pressurized Co2 http://greenleafaquariums.com/products/gla-gro-co2-system.html
hey Dutch, do you have an opinion on this system?
https://www.bigalspets.com/ista-co2-aluminum-cylinder-set.html
 

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