AquaticTechTank.net

I don't know why I didn't make a connection before but I was thinking about my high tech 75 g with sand substrate.

I built a co2 sensor and measured co2 in my high tech tech and low tech tank. I noticed that when the co2 tank was off, the co2 dropped down to 2ppm while the low tech 10g tank with black caribsea, porous lava rock thing (flora max) had co2 in the 20s ppm. It drops during the day as the plants consume the co2. I have mineralize dirt in both tank so they should have the same kind of organic under the substrate.


CO2 naturally occurs as a by product of bacteria activities. The porous rock substrate is superior in promoting bacteria, not so with sand. I have a feeling plain gravel is similar to sand. So the lesson is don't use sand for a low tech planted tank. I think I'm going low tech for my 75 so that means I'll have to get rid of the sand as well and get good porous substrate.

I've always thought substrate doesn't matter just as long as it's cheap and looks good but I am wrong.