Your investment threshold is the amount that you specify in Setup Investment Transfers; a minimum of $1,000. The threshold determines the amount that is pushed to your investments. With auto-investment transfers on, it will automatically send money over the threshold in $100 increments over to the investments. If the HSA account falls below the threshold, it will also automatically pull money out of investments back to the HSA account.
 
Transfers can be turned off at any time by re-entering the Investment Account Setup screen and selecting “No” to auto-investment transfers.