Originally Posted by hywaydave
Thanks Byron but you and I have discussed this before. I only have two T5 bulbs now, I run them 6 hours a day, do 20% water changes per week, and add Excel Comprehensive the day after the water change. Plus I put fertilizer tabs under the gravel near my 3 amazon swords (1 tab each) every 3 months. What am I doing wrong? Is there a test kit I can use to test the amount of micro and macro nutrients available in my tank? Should I stop using tap water and get a RO device? I do occassionally put the recommended dosage of Flourish in my tank when I think about it, maybe once a week. Do you think that fluctuation in carbon could be causing the BBA?
First, generally speaking, any fluctuation from week to week with respect to plant nutrients (those being added) is going to cause problems for the plants, and algae is always waiting to take advantage of this.
So the first thing, is a regular program of adding whatever one adds. Otherwise, you are always going to be basically fighting uphill. And I'm here obviously referring to liquid additives; the substrate tabs once every three months is fine, I do that for my larger swords and the lotus plants. But plants are continually assimilating various nutrients via their roots and leaves, and if these run out the plants have no option but to slow their photosynthesis and in severe cases even shut down. This is why the balance is so important between light and all nutrients.
Now to specifics, if the previous discussion was in this thread http://www.tropicalfishkeeping.com/a...-doing-109345/
and the tank and light is the one mentioned therein, I must say that I consider this too much light intensity. Reducing the duration as you have done, and having a good layer of floating plants, is about all you can do. From what you say, this doesn't seem to be sufficient, or the brush algae would not be a problem. But here I should ask, just how much of a problem is it? If it is on the plant leaves, and increases on the plant leaves noticeably, that is a problem as it will suffocate the plants. But if it is just on wood or rock decor, I leave it alone. My wood in my tanks is covered in brush algae, and frankly it looks quite lovely; and the fish are forever browsing through it searching for microscopic live foods and finding them. So use the plants as the indicator.
I don't advise using Excel; Seachem admit they don't know why it sometimes kills brush algae, but if one considers the sole ingredient this is not too surprising. I wouldn't want this in my fish tanks. Flourish Comprehensive is fine, once or twice a week; with your light I would suggest at least twice, and maybe three times, but at regular intervals. I am now dosing Flourish three times weekly, two days apart for each. But I have less light intensity than you have over my larger tanks.