Algea problems, could use some advice on C02 and Ferts

Actually you really don't have enough light. See Rexgrigg.com for an explanation on lighting smaller tanks.

On just a 20, you could do DIY CO2 as a cost effective option or go ahead and spend the money on a pressurized system. It's all based on your budget. Rexgrigg.com also has information about building regulators for pressurized CO2. Rex also offers them for sale.

http://www.theplantedtank.co.uk/algae.htm is a great guide for diagnosing algae problems and fixing them.

For ferts, once again check rexgrigg.com.

I suggest Rex's site because he's very helpful, I use his products, and they work great for me.

Excel has algaecidal properties - so not only is it a good carbon source, it's detrimental to many forms of algae.

Get some faster growing plants that will uptake nutrients. Hygrophila, anacharis and water sprite are monsters in good growing conditions and will give the algae strong competition for the nutrients.

Go with the CO2 if you can. It can't hurt (though I personally think it's overrated as a form of algae control.)

But otocinclus cats and Siamese algae eaters! Not only are these guys useful in the algae war, they are really cute too.

And finally, you are in somewhat lower light conditions. Add another fixture and double the output.

I would highly recommend using the Excel everyday and start injecting CO2 as soon as you can. The combo works well with DIY as the Excel helps offset the uneven CO2 levels that come with DIY. I would also manually remove as much as you can.

I would also start an EI dosing plan as soon as you can. I add a 1/4 tsp on potassium nitrate, a 1/4 tps of potassium sulfate and a 1/16 tps of phosphate every other day. On alternate days I add a 1/16 tps of trace mix. I do a 50% water change every week.

I do not agree that your tank is lowlight. I have 20 gallon long with 65watts as well and it acts in every way like a high light tank. Anything I put it in grows well, the plants pearl everyday and grow like weeds. Same as my other high light tanks.

I see the point that the Rexgrigg site makes but I don't think it takes into account the success of many many aquarists that have had great success with much less light on small tanks.

One thing the article doesn't mention is that sun in the tropics has varying intensity. Plants in the tropics may only get those 140,000 lumens per sq. meter for a half hour (who knows?) a day. Our tanks are more binary in nature, lights (in most cases) are on or off. But I digress...

When you go to a bigger tank you may want to consider some biological weapons (algae eating critters) as well. For truly nasty algae problems, my best results have come from matching an algae with a critter known for eating it along with proper ferts.

Also, switching to a bigger tank may give you a chance to give your plants a "dip" in a dilute bleach solution or some other more drastic approach (won't fix the underlying problem).

</end rambling>

Nature and horticulture are two very different things.
Careful not to equate the two or assume that it is "preferable", "better" to mimic nature to achieve a horticultural goal. Plants grow in nature because that's the only place they can grow at that time and space, not because that is what is "best" for them.

The light at 65w for a 20 gallon is plenty.


Regards,
Tom Barr

In addition to use of Excel & DIY CO2, you should consider adding a N source as dosing micros isn't going to do you any good if you leave macros (2 of the 3) in short supply.

See www.rexgrigg.com or APC for more details... you also may be interested in plantbrain' site www.BarrReport.com

I only know that my experience with 65w over a 20g long disappointed me into adding a second fixture. And the results were very apparent.