Diana K

Yes, that helps.

x,xxxK is a way of saying what color the light will look to our eyes, it is a blend of wavelengths that seem to look like that. When planted tank people were just starting to understand what plants needed the big push was for bulbs that were labeled 6,500K. Numbers lower than that tended to have more red, not enough blue for optimum plant growth, though bulbs down to about 5,000K seemed to do OK. Higher than that, some tanks looked fine, descent plant growth at 10,000K (very blue, not as much red).

Now we look for a chart that shows how much light the bulb puts out at different colors. A 'plant and aquarium' bulb will usually have a high output in the red and in the blue, at just the right wavelengths for plants. This sort of bulb looks sort of pinkish purple to us.

I think the bulb you have probably has almost no blue, and probably looks warm-yellow.

vicky

Oh I definitely prefer the look of daylight, or the 5,000 to 6,500K bulbs. But the plants? They don't seem to care.

Walstad used a 14 watt "Bright White" bulb. I would guess it might have been in the 4-5,000K range. And she had it mounted vertically, like you do. Surprisingly, that makes a big difference, according to this guy with a par meter: http://www.plantedtank.net/forums/li...r-bulbs-2.html . But, she had the light centered over two bowls. I'd guess that your 10 watt light is just fine for the plants, even if it looks a bit yellow to our eyes.

Over time, if the plants seem to need more light, you can put a higher wattage bulb in it. If it seems like too much light, you can just raise the light a bit higher.

Getting plant cuttings from a local is a great way to start. They are more likely to have been grown submersed, and more likely to thrive in your tap water. You might be lucky enough to have a hobbyist aquarium club in your area, but joining one is probably the quickest route to MTS - Multiple Tank Syndrome. It's a fun disease, so go ahead.

Douglas Ingram

I also find that swordplants do better in warmer water than cool. I have some in tanks in my shop that are room temperature, ie not more than 20C and they are struggling. I have some in a heated tank in the house and they are doing magnificently. Mind you, there may be other factors too, but this is an obvious one.