Quick question about cycling

[Whisker Wrangle]

Hey guys while cycling a tank should the lights be left on or off? Or should the tank be kept on a normal light schedule?? For some reason it seems like I read to keep the lights off but I am still in phase 1 waiting for the ammonia to drop and it has been well over a week. Just wondering if the lighting had any reason for this, or is this a normal amount of time to wait? It is a brand new 36gallon. Thanks for the help.

 

[Haydn24]

Lighting has no affect. Just keep a constant temp. Your cycle will start soon. Keep testing for nitrite good luck

 

[theicequeen]

Just do they lighting as normal. Is it a fish-in or fishless cycle?

 

[KarlTh]

And how have you introduced the bacteria?

 

[Whisker Wrangle]

Fishless. Added 5ppm ammonia about a week and a half ago. I will just keep checking. Temp is at about 76 I think. Should I raise it?

 

[jpappy789]

I would.

The only reason I see to turn the lights off is that you don't need them on so might as well save the energy and bulb life.

 

[GotTanked]

Keeping the lights off will help reduce algae forming during the cycling phase... but it's not important :lol:

 

[KarlTh]

Fishless. Added 5ppm ammonia about a week and a half ago. I will just keep checking. Temp is at about 76 I think. Should I raise it?

But you've not added a bacterial source? In which case it's "how long is a piece of string".

 

[DocTim]

There is a scientific reason behind keeping nitrifiers in the dark so to speak.

Here is an abstract about the effect of light on ammonia and nitrite oxidizing bacteria

ABSTRACT: Nitrifying bacteria (NH4+and NO2- oxidizers) are capable of recovery from photoin- hibitlon in the dark. After short-term (2 to 4 h) irradiations, significant differences were found between the 2 groups. NH4+ oxidizers subjected to longer wavelengths (>400nm; 25 W m-2)or polychromatic light (15 W m-2)regained activity faster (0.5to 1 h) than if exposed to shorter wavelengths (<400 nm; 25 W m-') or sunlight (360 to 400 W m"). In contrast, NOz- oxidizers only failed to recuperate activity after sunlight and near-UV (300 to 375 nm) treatment. Artificial light (5 to 25 W did not affect nitrite oxidation. Thus, recovery of NH,+ and NO2' oxidizing activities exhibited both dose and wave- length dependencies. These distinct recovery responses imply that nitrogen turnover in aquatic ecosys- tems depends on a number of factors among which light transmission properties of different water types (i.e.from lakes, rivers, estuaries, coastal marine and oceans) and physiological differences between nitrifying bacteria play significant roles.

These researchers did test ammonia and nitrite oxidizers in artificial light and found nitrite-oxidizers to be unaffected. However, ammonia-oxidizers were negatively effected - especially by blue light. Here is the abstract:

ABSTRACT: Spectroscopic analysis of nitrifying bacteria revealed the presence of a porphyrin-like pigment with an absorption maximum at 408 nm. The photoresponsive pigment accumulated during the late exponential phase of growth. The photoreceptor was found at higher concentrations in NH4+ oxidizers than in NO2- oxldizers. When absorbance scans and action spectra of the nitrifiers were compared, it was found that the regression between the degree of photoinhibition and higher absorbances at 408 nm was significant (r2= 0.7). Reversible light-induced absorbance changes were observed in vivo and in vitro. Absorbance changes were maximally elicited by light in the 400 region for both types of nitrifiers, but the change was only significant (p<0.05) for NH4+ oxldizers.This spectral sensitivity of the NH,' oxidizing process suggests that the absorbance change observed is related to the blue light sensitivity of NH4+ oxidizers.

As long as you are not using actinics you should be ok but to be safe I would suggest limiting the light if you can during cycling.

 

[jpappy789]

Huh, was not aware of that...thanks for the excerpts!