After cycling my tank in near record time, with no "enhancers" I learned that ammonia, nitrates and nitrites aren't the only concern for water chemistry. I cycled with 3 White Skirt Tetra's in just 11 day's, supposedly. I added 3 Silver Tipped Tetra's on day 11 and 4 Cory Panda's on day 17. Two Cory's died within 48 hours, a third after 72 hours. One of the Silver Tip's died this morning, day 22. My pH is 8.4 and my kH (water hardness) is over 300. I added fish too fast, and didn't let my pH and kH "mature" to more resonable levels. I want to add more fish, but won't until the total water chemistry is good. The fish I have seem fine. I did a 17% (5 gallons) water change with RO day 18 and 4 cups of strained rainwater,pH 6.8, last night. Fish are on sale for 40% off to the end of the month, but there will be other sales. Now I must wait, and be patient. Gunnie told me to wait to add fish. Too bad I didn't heed her advise.