No, a Power Compact bulb has a different pin setup than a flourescent tube, and is more power-consumptive. Power compact bulbs require fittings designed specifically for them in either a straight-pin (4 pins) or square-pin (also 4 pins) connection arrangement. If you are looking to get a PC
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An actinic bulb (peaks in the blue and ultraviolet ranges of light) does nothing whatsoever for plants, and tends to lead to algae problems. The blue and ultraviolet light it produces is not suitable for plants, as these require principally red, yellow, green light. I'd reccomend against it unless you're going for looks, and have a great tolerance for scrubbing away algae. Same goes for 50/50 bulbs, as these are half actinic. Kelvin rating (e.g. 10000K), btw
, is a way of rating the color of light that a bulb produces. 5000-10,000K bulbs are appropriate for planted tanks. Most enthusiasts tend to prefer 5500Ks, 6700Ks (most popular) and 10,000Ks.