squidsagirl420 said:
That is probably more than sufficient light. I often say that watts is not a reliable measure of light intensity because of all the different types of lighting we have today, but here with 36w of CF over a 20g, I would expect it to be adequate if not over.
Flourish products have recommended doses on the label, and they say once or twice weekly. We are again back to the balance; the fertilizers dosed must be in balance with the light for the needs of the plants. Algae will take the advantage if either is under or over the level to balance out. I tend to start out with once and after a few weeks use the plant's response to add a second or not. But I also use Flourish Trace as well as the Flourish Comprehensive. And not every tank is dosed the same with either (or both), because of the plant species or numbers or lighting. Each aquarium can be unique. The plant's response as well as algae is the guide.
Just to illustrate how finicky this can be...in my 90g I found that dosing Flourish Comp twice a week caused brush algae to begin to cover the leaves of the large sword. Cutting it back to one dose stopped the algae increasing. I moved up to two doses again, and the algae began to increase. These tests were for several weeks, and several weeks apart; the sword plant sent out about 6-7 new leaves during the periods and these leaves remaining free of algae or becoming encrusted was the guide. There is no doubt in my mind that the algae was responding to the increased fertilizer which obviously was not being used by the plants. However, the floating plants and the red tiger lotus in this tank clearly were being underfed, so instead of a second Flourish Comp dose, I went to one of Flourish Trace. Plant response was quite noticeable after a few weeks, while algae did not increase. In this same tank, I also added Flourish Iron instead of the second Flourish Comp., but the same algae problem surfaced. What all this demonstrates is that plants have a fairly specific requirement for the 17 nutrients, and these are in a sort of proportion to each other, and this is governed by the light intensity. Sometimes increasing one nutrient can cause plants to actually shutdown the uptake of another. We may not see this, but when algae begins to increase it is usually a sign that such has occurred.
Byron.
So, I'll have very little time to check it out before heading off for business.
The fish are dealing with the light just fine, except for my pearl gouramis, who are still rather timid. I'm hoping as they get used to the tank they'll be more outgoing. I also figure as the plants grow more that it will help them feel more secure as well.
