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CO2 vs Flourish

1833 Views 9 Replies 5 Participants Last post by  kurosuto
I was just wondering, what is the difference between the two and can one survive on just either of them. (A 12 Gallon tank).

flourish excel btw...not sure if that makes a diff.
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CO2 is carbon. Carbon is the basic building block from which all life is created. The flourish provides mineral nutrients. CO2 is also a nutrient but of a different sort. Co2 gas gives plants a usable source of carbon. Mineral nutrients & carbon are converted by the plant into actual plant matter. Without a source of carbon, little or no growth can take place.
Low light tanks very rarely benefit from additional co2. The general way it works is the more light you have, the more energy the plant will have at it's disposal. The more energy a plant has to use the faster it can convert mineral nutrients & co2 into plant matter. A deficiency in any of these , mineral nutrients, carbon or light will result in slower plant growth & possibly plant health if it is a severe shortage of any one of those things.

Unless you have lots of plants & lots of light I probably wouldn't be too worried about adding co2. You could always try using Seachem Excel instead of Flourish. It's essentially Flourish but with a liquid source of carbon for the plants to utilise. I've heard of people having trouble with it through over dosing so if you try the Excel just make sure you don't overdose. It can put your fish at risk of oxygen starvation.
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o00 alright. thanks. please closed thread.
Hi Kurosuto,

Just wanted to chime in to recommend you do some reading on this board. It's a lot of info when you start out with planted tanks, but you can go step by step... for example, enter excel into the search box and you should get some good discussions about Seachem Excel.

In other words, take everything you read with a large grain of salt. Some of the info might be good, some might be entirely off. :fish1: Everyone has an opinion, and it doesn't always go along well with little things like facts.

Anyway... just to add another opinion - Seachems Flourish Excel is considered a CO2 replacement for smaller tanks, and it can work well. Besides Light, CO2 or Excel, you should also read up a bit on nutrients (macros and micros).

Without knowing more about your light levels and goals (high tech/maintenance or low) it is difficult to give specific recommendations, so you end up with a lot of generic babble. :smile:
lol thanks. i understand. Gonna be ordering excel+a bunch of micro/macro from aquariumferts.

also, im reading the EI sticky right now. so hopefully, iit'll guide me in the right direction.

aquarium is 36watts over 12 gallon with ADA soil. Btw, what is the deal with an air pump in a planted tank? is it recommended? not recommended? I want to get a reticulated hillstream loach from planetinverts so yeah..
Keep in mind when reading the EI stuff that this applies to planted tanks with high levels of CO2 (30 or so ppm). If you don't use CO2 just scale the dosing back a bit. Initially learning about your water parameters and testing a few of the key parameters doesn't hurt.

With regards to air pumps, they are not really necessary, and in CO2 injected tanks they work against you, because the surface agitation removes some of the CO2 that we are trying to get into the water. It's like driving on a cold day with windows down and heater full blast. :tongue:

If you don't inject CO2 and like the bubbles, it doesn't hurt anything. On the other hand, little pumps like the Koralia or any powerhead can add more flow without being noisy and creating calcium deposits like air bubbles would.
Excel is going to be my only source of carbon. If its not enough, then Ill probably gonna couple it with DIY Co2. Unless I can find a way to incorporate paintball tanks into the injection since i have a few of those.

Will the plants release enough O2 for the hillstream loach? they need high levels of oxygen.
A air stone ran while the lights are off will work for extra oxygen even with C02 injection since it doesn't work without light anyway.

- Brad

Q: Is Flourish Excel a replacement for CO2 in a planted aquarium?

A: Yes and no. It provides the same benefit as CO2, i.e. it provides the plants with a source of carbon for growth just as CO2 provides them with carbon. However CO2 by itself will give you quantitatively more growth than Excel by itself, although Excel does provide a substantial amount in comparison. If CO2 is a 10, Excel is a 6-7. Using both together provides additional benefit. One of the advantages of the Excel is no up front equipment costs and complexity of valves, hoses and regulators, etc.

Q: Will an airstone or surface agitation decrease the effectiveness of Excel as it would decrease the effectiveness of CO2 injection?? What effect would an airstone/agitation have on Excel's effective CO2 levels?

A: An air stone or other surface agitation will not impact the effectiveness of Flourish Excel. Flourish Excel is not CO2, it is simply a readily available source of carbon. This is an intermediate source and more readily available than CO2 and will not interfere with the uptake of CO2 as a carbon source.
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lol didnt see that! thanks. Guess that answers all of my questions. Darn it. So it is not enough CO2...Well, with excel then, what bubbles per min should I aim for, in a Co2 injection? if anything, I guess I'll have to use DIY CO2.
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