low vs high light

[Jambot]

When researching what plants to add to an aquarium, I always come across varying light requirements for different plants. They always rate them on a scale from low to high, however, they never say how much light is considered low or high. I was wondering if anyone here could enlighten me just how many wpg is considered low and how many is considered high.

I'm converting my 10 gallon aquarium into a planted tank soon. I have two light fixtures, each at 18 watts, bringing me to a total of 3.6 wpg. Now is this considered medium, high, or what?

I also understand that it's a good idea to have some sort of CO2 system with high light. I have my DIY CO2 ready to go once I get some plants

[smaug]

If that is from a quality correct k rate bulb [5500-6500k] then 3.6 is on the high side,but not terribly so.You can grow some very nice plants at that level as long as you have a good substrate and fert schedule appropriate for your plants.With a 10 gal choose plants that will stay compact without excessive trimming such as chain sword,dwarf sword,ozelot sword ,diandra,baby tears,rotala.You can do a fine job with seachem excel as your co2 source.

[gunk]

just to expand upon smaug's post, usually under 2 wpg is low-light, 2-4 wpg is medium and 4+ would be high light. for a 10 gallon tank, 3.6wpg should be fine for most plants as long as the color temp is about 6500k. DIY co2 should be fine, but I've always used Excel in my planted 10g and it's worked wonders.

[W_Oz]

WPG breaks down for small tanks. 3.6Watts in a 10 Gallon tank looks almost nothing like 3.6Watts in a 55 gallon tank. Something Rex ([Only Registered Users Can See Links.]) was talking about having to do with surface area of tank vs. watts vs. lux.

In order to achieve the equivalent light output of 3 WPG in a 55 gallon tank, a 10 gallon tank would need to have over 70Watts on light on it.

Just some food for though. Having said that, my GF's aquarium has a 65Watt CF lamp sitting on it and its about as bright as my 55 with 136Watts sitting on it.

[Jambot]

Yeah, I have four 9 watt 6700k bulbs. Sounds like I should be good to go. However, I have sand substrate, so no nutritional value there. Should I be dosing with fertilizers like Seachem Flourish, or maybe get some root tabs?

[Sasquatch]

What W_Oz said is important, small tanks have problems with getting high levels of light. I know, I have a 10g and a 5g planted tank.

That being said, small planted tanks work just fine. At 36w, you're on the low side, even if you have 3.6wpg. On my 10g I have 52w and have trouble with medium to high light plants like pennywort.

I use Seachem Flourish and Excel as well as Nutrafin Plant Gro to fertilize and have Flourite as a substrate. Things are growing like mad in there. No CO2.

Sand could be a problem since it compacts and can limit root growth. If it's possible, I'd replace it with something coarser with a grain size of 1-3 mm.

Good luck and keep us posted.

[Jambot]

Hmm, well I guess I can ditch the DIY CO2 and transfer that over to my 20 gallon. I'll just stick with excel for the 10 gallon and get some lower light plants.

Thanks for the help and info, guys, much appreciated. I'll see about posting some pics when I get everything in order.