Dosing nitrates (KNO3) to combat cyano

[paddyob]

Originally Posted by Jakegr

Proven method: Turn off your lights for 3 days, or only light the tank with blue light for 4-5 days (cyanobacteria do not absorb in the blue part of the spectrum). This is not long enough to harm corals, but the cyano will die off.

Prove by who? Could you post the link to the scientific study?

It definitely did not work for me. I ran only Blue+ for over a week and it had zero effect.

Unless by blue you mean Actinic, which has little value to any tank, and which most people are no longer using as better lights have replaced them.

Sorry, but this did not work for me. Cyano is a bitch.



I say Manually remove daily. Chemi clean is a bandaid you may have to redose again.

Try Chemipure Elite.

It is great. Give it a read. It takes about 6 weeks but the product lasts for about 6 months in your tank before replacing.

[Jakegr]

Originally Posted by paddyob

Prove by who? Could you post the link to the scientific study?

It definitely did not work for me. I ran only Blue+ for over a week and it had zero effect.

Unless by blue you mean Actinic, which has little value to any tank, and which most people are no longer using as better lights have replaced them.

Sorry, but this did not work for me. Cyano is a bitch.



I say Manually remove daily. Chemi clean is a bandaid you may have to redose again.

Try Chemipure Elite.

It is great. Give it a read. It takes about 6 weeks but the product lasts for about 6 months in your tank before replacing.

By blue light I do not mean "blue+" bulbs. Aquablue+ is a bulb type with an unfortunate name. It is a broad spectrum bulb that emits quite a bit of light above 500 nm, which cyanobacteria absorb readily. "Actinic" is not a scientific term either.

When I say blue light, I mean light in the 400 - 475 nm part of the spectrum.

Blue light, especially 450 - 475 nm, is immensely valuable to the vast majority photosynthetic organisms. It not only contributes to photosynthesis more than most other wavelengths (other than red), but it is needed for various other physiological functions, such as DNA transcription and blooming in terrestrial plants. Cyanbacteria, however, lack the pigments necessary to absorb light in the blue part of the spectrum.

As far as cyanobacteria not absorbing blue light, I can provide you with dozens. I'm doing a Ph.D. on phytoplankton at UBC and I have mini-library on my computer. Here are a few good reads on the subject. Wang et al., 2007 directly shows cyanobacteria does not grow under blue light.

Carvalho et al., 2011. Appl Microbiol Biotechnol. 89: 1275 - 1288
Das et al., 2010. Bioresource tech. 102: 3883 - 3887.
Wang et al., 2007. Biochem eng. 37: 21 - 25.