Is2 was more Nickel tolerant than expected, and only showed no real difference whether there was or wasn't heterotrophs. 

Is35 was fairly Nickel tolerant on it's own, but ACW3 saw Improved nickel resistance in the 100µM range.

Neither culture was able to survive in the 100µM range, but within the 50µM-75µM range there was evidence that Fe27 heterotrophs Improved survivability.