I recently posted in another thread about my experience with the milky/cloudiness issue of eco-complete bags as of late.
eco complete help!
Well today I discovered another issue with contaminated eco-complete that could pose severe problems to people who use it, especially those who are new to planted tanks. I recently set up a 125 Gallon tank using eco-complete in which 4 of 12 total bags were contaminated with the milky white substance. I was getting ready to fertilize this tank for the first time and decided to test Nitrate and Phosphate levels first. Nitrate was normal for what normally comes out of the tap. However, upon testing for phosphate, the test showed levels of phosphate that were off the scale. I immediately tested water out of the tap to rule that out and it showed about 0.5ppm of phosphate. My next suspicion was the eco-complete. I still had two unopened bags of contaminated eco-complete, so I opened one and drained about 16oz of the milky liquid into a dixie cup. I then filled a bucket with 1 gallon of tap water and tested it for phosphate as a control. Phosphate, as predicted showed about 0.5ppm in the control. I then used a syringe to extract 5ml of the milky liquid from the dixie cup and added it to the 1 gallon bucket. I tested the mixture, and sure enough the phosphate level was through the roof. (Past the top 10ppm limit of the test kit) I rinsed the bucket and repeated the experiment, first with the control test which again showed 0.5ppm of phosphate. However, this time I had filled the bucket with 2 gallons in hopes of getting a more dilute sample. This time around I added only 1 ml of the milky liquid to the bucket and tested. Finally I could get a reading within the range of the test kit which read at about 5.0 ppm. So basically a mere 1 ml in 2 gallons of water can raise phosphate levels to fairly high level. Imagine adding an entire bag which probably has at least 32oz or so of this stuff to your tank.
Here's another thread which may provide some answers to this: Corrupted Ecocomplete
This thread mentions that at some point calcium carbonate had gotten into several lots of eco-complete resulting in customers having high GH and KH readings. I found this to be odd because in my case, as I mentioned in the first thread, I ended up with a large drop in pH which is basically the opposite of what the others had experienced. Later in the thread, Del points out that after Caribsea learned of the high GH/KH problem they started adding a clarifier to fix the problem. Based on all this information I'm led to conclude that in addition to the "clarifier" or perhaps as part of the "clarifier", Caribsea added a large amount of Phosphate based pH Down/Buffer type product to counteract the effect of the Calcium Carbonate....
I'm sure they meant well in doing so, but the side effects could have major impact on people who are new to fertilizing. Faltering with other ferts with this level of phosphate could definitely lead to some major algae problems. I'm sure this would also invalidate the pH/KH CO2 chart. Don't get me wrong, I love eco-complete and highly recommend it. I just wanted to let everyone know to be wary and to avoid using the contaminated bags unless you rinse them really well. Caribsea seems to have shown great customer service as evidenced in these threads and I'm sure they'll resolve the problem in the near future.
PS: If anyone else has contaminated bags right now, it would be great if you could test your bags to see if you get similar results.
Here's a pic of the test done on my tank water that prompted all of this.