Here is a little update for those that have been helping. The test still read 0 for phosphate and nitrate. I tested them on my city water and had valid readings, so I know they work. However, I feel that there are some phosphate and nitrate available below the readings. My acropora has exploded in growth and the color has also been coming back. I have a birds nest that has doubled. The tips grew back on another. The hammer has been slowly coming back. The frogspawn has grown new branches. All of the zoanthids are doing well. The ricordea is doing nicely. All I have done is remove the gfo, add two fish, and dose strontium and iron. Now, my only problem is that I have three montiporas and only one has responded. The other two are not growing. One looks great but hasn't grown a centimeter. The other looks pale and may be bleaching. The one that is bleaching used to maintain, but not grow. now it is going poorly. I have read in the past that gac cleans up chemical warfare from the acroporas. At this time I do not use carbon. If this was the case, wouldn't the third monti be doing poorly?