Is it possible (practical) to run a tank with low levels of co2 ,10-15 ppm, without algae problems ? If so how would it be done ?

Henry

Try 1.5 to 2 wpg. T5 compact fluorescents @ 6700k on a 10/5 hr. split cycle. 1/2 dose EI. GH 5 and KH 4. Here's the trick...You'll want to 2 Farlowella Acus, 3 SAE's, 6 Otocinclus, 2 corys, 10 Amano shrimp, and 20 Red Cherry Shrimp. Mind you this livestock is per 20 gals !

As with all things your mileage may vary... Good Luck, HTH. Prof M

That and fairly stable CO2 supply, stable is the key.
Some plants will not enjoy the lower CO2 and grow as well as they cloud otherwise.

Common sense suggest that plants have preferences for richer nutrients, however, all plants will do well in rich nutrient levels, but some are fairly aggressive at lower nutrient levels and thus do quite well.

So generalizations are just that, very general and you will run into exceptions.
Just keep that in mind when bending the rules a little so to speak.

Regards,
Tom Barr

My original reason for posting was that I'm thinking of setting up a 20 gallon tank. I like to use co2, but don't want to spend the money to set up a pressurized system for a small tank. I was concerned about the level and stability of co2 in a diy co2 setup which I was thinking about. Would the addition of excel in a tank with low levels of co2 help to stabilize the system ?

Henry

Excel alone can be done easy enough.

I suggest one of those DIY CO2 internal reactors I described how to make.
Make one, add DIY CO2 to that, add light etc/nutrients, change the brew weekly, you will have no issues with CO2 on a 20 gal tank.

They are very effective for DIY CO2 and designed around that source, but also work very well with canned cO2 as well.


Regards,
Tom Barr

As Tom already stated "Stability" is the real key to yeast reactor Co2 systems. I use a two bottle system 1 week apart, and rotate 1 bottle out and forward weekly. This combined with Tom's DIY reactor can actually supply some fairly respectable levels of Co2. The Alcotec Turbo Yeast primed with o2 is a quick high yield, alcohol tolerant yeast I highly recommend. HTH. Prof M

Where can I get alcotec turbo yeast ? In the past I prepped yeast in a dish with tepid water and a little sugar before dumping it in the sealed bottle ? Is this the o2 reference you made ?

Try Here ! Turbo Yeast - home distillation - alcohol 24 hours

An o2 boost is a brewers trick to accelerate fermentation. You simply pump in a good shot of tanked o2 before you cap the bottle. Yeast utilize the ambient o2 in the bottle for conversion. The more o2 the quicker the conversion ! Savvy ? Hardly neccessary, but very most definitely effective ! LOL.

I ran 100w of PC light over a 20 gallon for about 10 years using the reactor and the 1 x 2liter DIY CO2 with plain old yeast and sugar.

So if you have less light, it's not likely you need more CO2.


Regards,
Tom Barr