You have 2 major issues working against you:
1) 2x18 normal fluorescent bulbs HARDLY offer enough light for even very very low light plants.
2) 18,000K bulbs are not plant appropriate.
For this tank, you will want to shoot for atleast 2wpg. You can do this with a 2x55 Power Compact light setup. I always DIY it a little and go with www.ahsupply.com
For bulbs, get something between 5000K and 10000K. 5000 is more yellow, 6700 is more green, 10000K is more blue.
There are also GE 9325K's which look pinkish, but are wonderfull for plant growth.
1) 2x18 normal fluorescent bulbs HARDLY offer enough light for even very very low light plants.
2) 18,000K bulbs are not plant appropriate.
For this tank, you will want to shoot for atleast 2wpg. You can do this with a 2x55 Power Compact light setup. I always DIY it a little and go with www.ahsupply.com
For bulbs, get something between 5000K and 10000K. 5000 is more yellow, 6700 is more green, 10000K is more blue.
There are also GE 9325K's which look pinkish, but are wonderfull for plant growth.