I am going to have to disagree with these statements (which I gather are from the linked website).
1) No need to exchange T8 or T5 lamps every year. Use them till they die and save yourself some bugs. (Yes they will lose a little output (about 10%) but its not enough to justify some early exchange)
Fluorescent tubes do lose intensity, and much faster than 10% over a year. T8 and T5 are different in their composition, but every planted tank source I have come across has recommended replacement of T5 as well as T8 long before the tubes actually burn out. I have experimented with T8 and I found that basic tubes (the less expensive but often suitable Daylight 6500K tubes like GE, Sylvania or Phillips) in 48-inch length need replacing no less than once every 12 months. The more expensive aquarium-specific tubes like the Hagen Life-Glo will go a bit longer, but in my case I found they had weakened sufficiently at 15 months the plants began to show it, and algae increased. The algae is a sure sign of weakening light, since it can make do with less light than higher plants.
I replace all my T8 tubes every 12 months. When the new tubes are turned on, there is a noticeable brighter light, and if I can see it, so can the plants even more.
2) Most "special" lamps (only talking about T8 and T5 here) are simply re-branded standard lamps. And the few lamps which indeed are different and are especially designed for aquaria are in practice still not significantly better than standard lamps (better spectrum but less light), meaning they are not worth the money at all either. So save and buy standard lamps if you need replacements.
This is partly true, but needs explaining, as it is not universal. It is certainly true that "aquarium" or "plant" tubes sold in fish stores are often weaker intensity, and can cause issues for plants and increase algae. But this is not the case with all aquarium store tubes, if you know what you are getting.
Over my larger tanks that take two 48-inch tubes, I use the less expensive Daylight tubes from Home Depot. Phillips and Sylvania both make a Daylight 6500K and a slightly warmer 5000K tube. This combo is ideal, as it is high in the red, blue and green wavelengths. And the 48-inch tubes are good value. I have tried the smaller tubes and they did not work at all, due to the intensity being too little by comparison.
Over m,y smaller tanks using a single T8 tube, I use a Life-Glo 6700K. This tube is twice the intensity of the Aqua-Glo in the same line, due to the phosphors. The Life-Glo is without question the best single tube in T8 for smaller tanks. Another identical is ZooMed's UltraSun at 6500K. There may be others, these are the only two brands I have found locally to try, and I will use either over my smaller tanks.
When a Life-Glo 6700K 24-inch was compared to a Phillips Daylight 6500K 24-inch over the same tank (each for several months) the plants began to die under the Phillips. There is no question that the intensity of the Life-Glo is much higher.
The spectrum of lighting is very important for planted tanks. Mid-day sun is somewhere around 6000K, so lighting in the 5000K to 7000K range should work best. This lighting also delivers a true colour rendition of plants and fish.
Byron.
