Originally Posted by denrgb
No nutrients as of yet. However I did plan on it. Light COULD be a problem though as we might turn the light off more than often. I am getting brown alae (which I know forms in beginning tanks with low light).
I'm thinking of getting a timer, to get used to a reef tank (which is my goal one day).
The problem is lack of nutrients. Plants need food every day, and their food is nutrients, 17 of them. Light will be of no value whatsoever if any one of the nutrients is missing. But algae will use the light and the plants will die off--and here I'm referring to green algae, not the diatoms you are seeing now. When the light tube diminishes too much, it is interesting that algae becomes more prevalent; the reason is that the plants can't use the light so they stop growing. Same thing happens with any nutrient. Plant growth is always as high as it can be with what is available in the necessary proportions. I go into this in more detail in the series "A Basic Approach to the Natural Planted Aquarium" at the head of the Aquarium Plant section if you're interested.
Some nutrients enter the tank via the water (calcium, magnesium, perhaps some others though water conditioners that detoxify heavy metals remove micro-nutrients like iron, manganese, copper, zinc), and fish food. But not sufficient to feed growing plants.
You need a comprehensive fertilizer, and I highly recommend Seachem's Flourish Comprehensive Supplement for the Planted Aquarium. It is the only one to my knowledge that has all necessary nutrients and in proportion to what plants need. Nutrafin's Plant-Gro also seems to do a good job from what others have mentioned here. Without fertilizer, your plants will not do well.