Flashing lightbulb is driving me crazy

[johnpeezy]

So every time I turn on the lights in my 20 gallon L the light flickers for about 5 minutes.

its just a regular florescent light fixture.

do you think its the starter or the bulb that needs to be replaced?

Also how much of a benifit will my plants get from getting on of those plant gro bulbs as opposed to the standard lights that come with the fixture?
do you think its worth the extra cost

[joephys]

best way to test it, switch two bulbs around and see where the flicker goes.

The gro bulbs aren't very good. The standard bulbs that come with the fixture aren't very good. If you want to get better bulbs, get ones with a color rating of 5000K-6700K. Home depot should have some called daylight or daylight delux that should be what you want. Much cheaper than the LFS.

[johnpeezy]

ok cool thanks,

Will switching my lighting affect my fish much?
its for my apisto gramma tank and everything is going awsome in there, plants are exploding (its right next to my sliding glass door) and everyone is trying to make babies so I don't want to upset anything.

[joephys]

It shouldn't. It may [but probably won't] cause them to hid a little bit for a day or two, but nothing major. If your plants are growing well, it might not be worth spending the money.

[TwoTankAmin]

If you are willing to spend a bit more, look for Tri-phosphor, daylight bulbs. I think CoralLife makes them in T-12 and Zoomed makes them in T-8. They are both high CRI bulbs, meaning they show colors accurately and you should find they really make your fish colors pop. Plants love em as well.

One advantage to the Tri-phosphors is you can run them until they burn out rather than having to replace them every 6-12 months as you should with standard fluors. In the long run they cost no more due to needed to be replaced less often.

Color rendering index (CRI)
The color rendering index identifies the degree of color shift objects undergo when illuminated by a particular light source. In simpler terms, the CRI expresses the degree to which a light source renders the true color impression. The CRI is an index and ranges from 0 to 100. A light source having a CRI of 100 means objects illuminated by it look like they're supposed to; that is their natural color is not distorted. A light source having a very low CRI would tend to make objects appear to be a different shade or even color that they really are. An example of light with a high CRI is, obviously, sunlight. Some fluorescent tubes such as Daylight, Chroma 65 or Vita-Lite have a very high CRI. Some light sources such as Gro-Lux or sodium vapor lamps have very low CRI's.

From: Artificial Lighting

[joephys]

Tri-phosphor just means that they use three different types of phosphors. I have never heard anything before that the "expensive LFS" types can go longer with out being replaced.

The given definition of CRI is misleading. CRI is a lot more complicated than that. Its based on comparing the colors that something is illuminated compared to a standard perfect black body radiator. Its generally something around 5000K, so the sun is often used as a comparison since it is somewhat close to that. It really doesn't work well with fluorescent bulbs because they don't produce a smooth spectrum of lighting, but peaks in specific wave lengths. Generally 3 large peaks and a few smaller ones with daylight bulbs. CRI doesn't give any meaning to the quality of the bulb.