I saw a banner ad for Dr. Tim's One and Only Nitrifying Bacteria on this site. Clicked on it out of curiosity and it appears to be a biological starter like Bio Spira. It was developed by Dr Timothy A. Hovanec who also worked on Bio-Spira. It appears that Dr Foster and Smith no longer sells Bio Spira but they sell the One and Only product. Marineland's web site no longer mentions anything about Bio Spira. Has Bio Spira been discontinued and is the new product, One and Only taking it's place? Has anyone used this new product? Does it work as good as Bio Spira?