cost analysis....CO2 methods - DIY vs pressurized vs Excel

[newfound77951]

When I started up my 55 gal planted tank, I researched various CO2 methods, and decided with my limited budget and limited DIY skills to go with an off the shelf yeast setup. I'm finding it's less than effective, so I started adding Excel as well, which definitely made a few differences (there's another whole thread on that...). I decided against a pressurized system in the beginning because of the cost, and I had heard several anecdotal thoughts that Excel was too costly to use long term in a large tank. But....

If 250 ml Excel treats a 55 gal for 1-2 months (let's say 1.5), then 1 liter will treat the tank for 6 months, and 2 liters for a year. 2 liters of Excel online at various places is <$25. With the initial cost of the yeast set up plus the ongoing costs of yeast/sugar refills, it seems like Excel is still a lot cheaper. Granted I could have built a DIY system for less, and this might be the cheapest alternative for small tanks. However, the amount I'll spend on Excel per year would take a long time to equal what I would spend on a pressurized CO2 system (say ~$300 initially, plus a small amount each year for refills...that's 8 years worth of Excel!)

So my point here is that maybe Excel can be a cost-effective method for "smaller" tanks, and that pressurized CO2 would come into its own on really large tanks (greater than 100 gallons or so). I'm not here to be an advertizement for Excel....if anyone knows of another product that works similarly, let everyone know, and if there are any long-term drawbacks to using Excel, also let all of us know! i'm just bringing up something I noticed that might be helpful for the newbies who are contemplating setting up a planted tank and are trying to make the vision in their head match with the money in their wallet....

 

[mr funktastic]

well it may seem cheaper but u can get much higher results witha pressurized co2 system than u can with the reccomended doasge of excel. plus u dont have to worry about remembering to dose the excell all the time. pressurized is just set it up and watch it go, no maintence beside checking it every once ina while. i see your point though. it has also been said on may threads that diy is only good up to around 30 gallons. any higher is to costly like u said.

 

[newfound77951]

I guess I should have said that I definitely agree that pressurized CO2 is the ideal method. There seems to be an intermediate tank size that is larger than the limits of a DIY system, but small enough that a pressurized system is a large percentage of the cost of the rest of the setup. This in-between range encompasses a lot of popular tank sizes, from 30-55 gallons, maybe even up to 75 gallons. Food for thought for a lot of people trying to decide what sized tank to get and how to outfit it.

I will admit the dosing every day is a pain in the butt....when I go on vacation I don't have to worry about feeding the fish (automatic feeder), but I have to get someone to "feed" the plants......but if you're dosing other ferts anyway.....

 

[mr funktastic]

u can buy liquid dosers that work in the same fashion as the feeders.

 

[Wizzard~Of~Ozz]

according to their dosage, on a 75Gal tank, 7.5ml / day so a 250ml bottle lasts 1 month, so 3 litres per year.

If you have a moderate to heavy planted tank, you must put it in daily (and possibly larger dosages).

a 2l bottle up here is 48$, a 4l bottle is 88$.. average would be 68$/year. after initial expenses my injection costs 15$ or less per year.

In reality that means after 6 years it's paid for itself. I also get the other benefits that come with Co2 injection (Pearling plants and a more comfortable PH For tetras)..

If you don't plan on having plants for longer then 6 years, then perhaps you are correct. otherwise it's a short term solution that over the course of 10 years will cost 200$ more and keep rising. plus in the event that you decide to get away from the plant hobby, excel has no retentative value, meaning I can sell my reg, Tank and Controller for 200$ or more

 

[czcz]

Also, even Seachem's FAQ concedes that Excel is not as good as true CO2. If your goal is great plants, the difference in quality makes up for the price/time imo.

(emphasis added)

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.

http://seachem.org/support/FAQs/FlourishExcel_faq.html

 

[malkore]

Wizard of Oz beat me to it ( I had to go find an empty Excel bottle).
You'd use 5ml per day on a 55gal to maintain it, and after a weekly 50% water change, you'd need to dose about 2.5-3 capfuls - 10-15mL
So that's 40-45ml per week, so a 250ml bottle lasts about 6 weeks and runs $7.

But more importantly, its a known fact, per SeaChem, that Excel will negatively affect some plants. Namely anachris and valisneria sp.

also, if you accidentally over dosed Excel, it can destroy your bio filter, and kill the fish. CO2 is harder to overdose, and has less drastic side effects.


One thing to note though, is that Excel does seem to give algae a kick in the pants. Seachem legally cannot advertise it as an algicide, but believe me, it'll nip certain kinds of algae in the butt.

 

[newfound77951]

This is cool....I just got a ton of great opinions and information on a subject that is still new to me, and I'm sure is new to lots of other people as well. I think I will continue with my yeast/Excel combo until I have the $$$ for a pressurized setup.

Thanks everyone for the information!