Several excel questions

**madagascariensis** · 10-01-2012, 11:21 PM

What would be the maximum amount of watts per gallon in an excel based tank that
won't cause any (major) imbalances? and additionally what tank
size would be, in your opinions, the maximum tank size where excel still is effective and/or economically viable?

**Lady Hobbs** · 10-01-2012, 11:26 PM

I would only use excel in emergencies to stop the growth of algae. I would not subject fish to it on a regular basis. When dosing with it, the oxygen needs to be increased.

**madagascariensis** · 10-02-2012, 11:11 PM

really? I have heard about many people who use it on a regular basis
and according to the manufacturer's instructions, thats what it is supposed to be for.

**smaug** · 10-02-2012, 11:41 PM

Originally Posted by Lady Hobbs

I would only use excel in emergencies to stop the growth of algae. I would not subject fish to it on a regular basis. When dosing with it, the oxygen needs to be increased.

Sorry but this is certainly not my experiance with it and I used it for years in fairly heavy doses. I know that your experiance with it were not good but I believe that has something to do with the chemistry of your water and not the chemistry of the product.
For OP,I used it heavily in a 58 gallon tank with near 300watts of pc and t5 lighting. The plants used varied over the years but at its thickest it had swords,hygro corymbosa,purple cabomba,round leaf ludwigia,dwarf lilys,dwarf water lettuce and a few apongentums sp. The growth was fantastic,the fish were healthy. I dosed about an ounce a day of excel along with the whole seachem line of liquid ferts . Its a safe product but some do have bad luck with it so start slow and dose lightly.

**homemadepopcorn** · 10-03-2012, 12:12 AM

Any tank size is suitable for dosage, just means that you'll be running out quicker.

Your question about imbalances:

Excel is a carbon supplement only, it lacks the other macro nutrients, Nitrogen (N), Phosphorus (P) and Potassium (K), and all the micro nutrients. Dosing only excel would be rather ineffective at increasing plant growth as you aren't providing everything that a plant needs to make use of the excess carbon.

I would recommend using a comprehensive fertilizing regime if you plan on using excel or else you're practically throwing money away.

Also, the nutrient demand for your plants will vary depending on the amount of light that you are providing. Too much lighting without enough nutrients leads to weak growth and plant decay as the plant is trying to process all the extra energy but lacks the proper ingredients to do so. Less lighting means that your plants will be healthy, but their growth will be slowed, and you'll be dosing extra fertilizer for no reason.

**smaug** · 10-03-2012, 12:30 AM

All true to the above for the most part Dosing light amounts of excel will provide a benefit even if no ferts are added provided there is a heavy enough fishload and feedings to provide nutrients.

**homemadepopcorn** · 10-03-2012, 01:01 AM

Touche salesman!

**madagascariensis** · 10-03-2012, 01:19 AM

sure, any tank size is fit for dosing excel, after all, water in a large tank is same as in a small one. I do know the more light=more ferts=more carbon rule, my question was more along the lines of "what is the minimum tank size where constantly dosing large amounts of excel becomes less economical than simply setting up a CO2 reactor?"

thanks for the help so far.

**homemadepopcorn** · 10-03-2012, 01:56 AM

Thats a really hard question to answer as there is no good way to compare CO2 injection versus carbon dosing in terms of economics.

IMO, you would use something like excel in smaller tanks where the daily dosage doesn't mean that you'll run out within the month...

Take my 29g for example... I does Easy-carbo, which is practically the same thing as excel. Its a dosage of 1mL/50L, so I dose about 2mL daily. It lasts months.

On my 90g thats being set up... 1mL/50L means about 7mL for the tank daily... in a month thats 210mL or about the whole bottle... and at $10 a bottle, it gets pricey.

A 20lb CO2 setup will run me about $250 but last the whole year or longer depending on the dosage and offers better more consistent dosing. Fills are $30 or so not including the initial equipment cost so thats a big savings over the $120 a year I'd spend on dosing the Easy-carbo.

Quick Breakdown for the 90g:

$10 per bottle x 12 bottles a year = $120.
$250 for the setup = $250.

Year two:
Another $120 for Easy carbo, only $30 for CO2. Totals $240, $280 respectively.

Year three:
Easy-carbo is now $360, CO2 is only $310.

These are just rough estimates but you get the idea. Plus, you can always sell off your CO2 equipment and expect at least 50-60% of what you paid for it.