Here is a first draft of an article I am writing for the article section in the "gregwatson.com" website. I am looking for the following feedback:

1. Is it understandable from a newbie's perspective?
2. Is it technically accurate?
3. I don't want to pretend that any of the theory in this article is mine because it's not. Therefore does it appropriately credit Tom's work?
4. Any and all other feedback welcome.


INTRO TO NON CO2 EXCEL TANKS
Having a planted tank does not have to be very complicated or very expensive. After a couple years in the hobby I have settled on a system which I enjoy very much both for it’s ease and for it’s simplicity. I am a fan of medium light planted tanks which use Excel as a carbon source. I currently have five of them. I have tried pressurized CO2, DIY CO2 and I have tried not using any carbon source at all but this is the system I enjoy the best. The primary source of the technical knowledge behind the system I use is Tom Barr’s article “Non CO2 Methods” at the “barrreport.com”. Please check it out if you want more detailed information.

Always start with the lighting. There is a generally accepted maximum amount of lighting which you can use on this type of a system. Anything over this seems to be asking for an algae bloom unless you add CO2. That maximum is 2 wpg of twin tube type compact fluorescents in the 5k to 10k Kelvin range with good quality reflectors. Now if the reflectors are not very good or if the bulbs are regular fluorescents then you could get away with more wattage because the effective light output is going to be lower anyway. The rule also tends to break down on tanks below 10 gallons because the size of the tank skews the formula allowing a higher watt per gallon ratio without CO2.

All my tanks are right at this maximum level. I like this level because it allows me to grow almost anything anyone else is growing - just more slooowly. The main limitation I have seen is getting the kind of red colors out of the plants that you see in the aquascaping contests. So I can grow Limnophila aromatica, Ludwigia repens and brevipes, Rotala indica etc. but I don’t get the intense reds and purples that some other can. I do still get some color just much less intense and sometimes it’s even only a touch of red. I have accepted this limitation and aquascape my tanks accordingly. There are some plants like Alternathera reinecki aka red temple and Myriophyllum heterophyllum aka red foxtail that do produce beautiful colors for me and there may be others out there that I have not tried.

You can use less light than 2wpg but then you do start to develop more limitations in your plant choices. If you do have lower light levels then you can use the “Plantfinder” at “aquaticplantcentral.com” which can be sorted by light levels so you can choose your plants accordingly. Remember that many of the plants can be grown at lower light levels than stated. They will just grow slower and without the intense reds.

The simplest way to dose is to base your plan on Tom Barr’s recommendations. Here is a sample dosing plan for a tank with a light fish load. This is from a thread on the “barrreport.com”:

So a 20 gal using excel would get:
2 w/gal light
Dose 1/8 teaspoon KNO3 1-2x a week
KH2PO4, 1/16th, 1-2x a week
Traces, 2mls 2x a week
SeaChem EQ 1/8th once a week
50% weekly water change
Dose 1.5-2x the rec dosing for Excel.

The KNO3 and KH2PO4 cover the macrunutrients of Nitrogen, Phosphates and Potassium. The traces and Seachem EQ cover your trace nutrients. The Excel gives you a liquid source of carbon. All of these are available at “gregwatson.com”. You can adjust these amounts based on the size of your tank. So a ten gallon would get half as much, my 37 gallon would get twice as much and my 75 gallon would get four times as much. Yes I know the math is not exact but it doesn’t have to be.

The 50% weekly water changes keep the dosage from adding up to more than twice what you are dosing. This frees you from having to do any testing.

Personally I currently use the regular dosage of Excel and do once a month water changes. Because of this I test once or twice a month for NO3 with a Hach test kit which I have tested against a fixed solution to check for accuracy. I adjust my dosing plan up or down based on those test results and my observation of the aquarium.

For substrate I have used Seachem Flourite and Seachem Onyx Sand. Both products have worked well for me but I definitely prefer the Onyx Sand. I like the color and the smaller size is a little easier to plant in. Whatever you use make sure you rinse it well. My initial use of fluorite was marred by massive cloudiness that required extensive filtration to clear up.

For filtration you can use whatever you like because you don’t have to worry about off gassing CO2 because you are not adding any. I like the hang on tank power filters for their ease of use and minimal expense. I use them with a sponge filter on the inlet and sponge material as media in the units. The initial sponge provides mechanical filtration and I clean it of debris every couple weeks. It also prevents baby fish or shrimp being sucked up by my filters. The other sponge media provides biological filtration. I like to size them so that I get plenty of circulation in the tank which keeps debris from building up and becoming a breeding area for algae. I find the HOT Magnum does well for this in my 37 gallon and my 2 55’s. I also have used this filter with diatom powder when needed to clear up green water or cloudy water.

While I wouldn’t guarantee that your tank will be algae free this system does safeguard you in several ways. The lower light limits and slows algae growth. The fertilizers encourage the plants to grow fast enough to outcompete algae. Excel seems to be able to limit and sometimes eliminate algae particularly at higher doses.

Thanks,
Bill

Looks good.

The only thing you might want to discuss is the differences of each CO2, Excel and non CO2 growth rates a bit more.

Many folks like the idea of some slower growth.

Less algae in general(less light and CO2 issues!).

The uptake rate is about 1/3 that of CO2, and about 2-3x that of Excel tanks.

You can also do as many water changes as you want with the Excel tanks if you chose to, or the less frequent ones you are doing.

Cost: larger tanks will cost more for Excel.

Regards,
Tom Barr

Hi Bill,

just want to correct my email. Newbies might like to know how much a teaspoon holds. As per Tom 1 teaspoon ~ 6,68g, 1/4 teaspoon ~ 1,67g


Regards,
Detlef

There is a fair amount of variability for each teaspoon measurement depending on the user, but that's close enough for most of us.

The mls volumes and other more accurate measures for Teaspoons and many teaspoon measurement spoons now have mls volumes.

The trade offs for each method are wise to discuss in any article for using carbon enrichment.

Excel is a good medium for those wanting a semi slow growth tank, moderate/low light, a few water changes etc.

Regards,
Tom Barr

I have read in the forums on seachems website that even though they don't like to admit it, may people have reported Excel in high doses will kill algae. I also saw a post that was inquiring about this also effecting simpler plants and mosses like it does algae. I just thought it might be nice to list some plants that don't do well with excel as well as those that do. Maybe Excel doesn't kill them, but maybe they just can't make use of it.

These posts got me thinking about something that has puzzled me for a while. I have multiple tanks. For plants I have anacharis, hornwort, aponogetons, water sprite and java moss. In a 10gal tank I have that has 2watts/gal compact flourecent lighting, and a heavy fish load all of these plants grow slow but steady. I do not add any fertilizers at all to this tank. On the other hand I have a 55gal tank with 2watts/gal compact flourecent lighting, and a light fish load. I have been using the entire seachem line including excel in the 55gal tank, since this tank was on display for all to see. For some reason the anacharis and hornwort just would not grow in the 55gal tank, even though the water sprite and aponogetons grew like there was no tomorrow. I recently switched from using excel to pressurized CO2 on the 55gal tank. A curious thing happened, a small piece of hornwort that was dieing slowly started to grow again. I haven't tried anacharis in the 55gal since the change but plan to soon. So I'm wondering if plants like anacharis and hornwort, just can't make use of Excel.

I am a wee bit concerned about your title. I DID read it right off as "... non CO2, 'but using' excel tank", but I suspect it could easily be read as "... non CO2 'and non' excel tank", because I wondered about it and had to read the article to see if you WERE or were NOT using excel.

I think I got it right -- you are using EXCEL instead of CO2??

Yes, folks add excel, but not CO2.
Excel dosing only.

Non CO2 tanks really leave out Excel dosing, since it's not really dosing CO2 (it is dosing CO2 at the cellular level as Excel decays into CO2 inside the plant).

Excel will not work well on Egeria, Hydrilla etc, they do not have stomata and are more like algae in their uptake of CO2 and HCO3.
And that's why they are very agressive weeds.

Regards,
Tom Barr

Bill,

I was interested in your article as I am interested in setting up an excel tank. Is the suggested dosage for kh2po4 2.7 ppm for 20 gallons ? I ran the numbers using Chuck Gadd's dosage calculator. Apologies if I made an error

Henry Hatch

This amount of PO4 works well, I've found errors with some calculators, I do my own. I would rather folks stick to the teaspoons as they make the entire process much easier and are fine, 1.5-3.0 ppm is fine for error for PO4.

You can get away with less water changes with the slower growth from Excel, but not do away with water changes completely like non CO2/non Excel methods.

I get good color in my non CO2 tanks though.
You can also use the ADA AS, or a sand cap and organic soil and/or manure that's been boiled or soaked for 3 weeks etc.

All these and the water column dosing method work well, you will have more nutrients to grow a non CO2/non Excel tank in well this way, but it's not required.

Main thing is when you top off the water, add some KNO3/KH2PO4/Gh booster and traces in(weekly or once every 2 weeks etc).

Also lightingm, you can grow most plants in non CO2 tanks with 1 w/gal of T5 and similar light with PC's provided a good spread of light(T5's are better here).

Example:
A 55 gal tank and 54 w T5 with good reflector.
A 20 gal with a 24" 24w T5 with good relfector etc.........

You will still gain from CO2 at these levels even.
Or you can opt for no CO2/Excel at all.

Regards,
Tom Barr

I like the article and the method, but one of the types of tanks people are very likely to use this method with is nano tanks. I just got a 2.1 gallon tank, and I'm planning to use this method for it, but......so much to learn first! So, lets start with some basics:
I have a 14 watt, 5500K screw in fluorescent light bulb in a small reflector that will be positioned above the open top tank. Is that enough or too much or not enough light?
With that light, and about 2 gallons or less of water, how much of what should I dose? And how often?
My substrate will be Soilmaster over a bit of ground peat and filter squeezings from my 45 gallon tank. Will that work ok?
The plants I plan on are anubias nana petite and Java Fern Windelov, both growing on a piece of driftwood. That will be about 1/3 coverage of the substrate. I plan on going to LFS for a bunch of something cheap and fast growing to add temporarily. Is that the right way to do it?
For filtration I will use an Azoo Palm HOB power filter. No heat.
Later, like a couple of weeks later, I plan to add a betta as the sole occupant, plus possibly an otocinclus. OK?