Little bit of sell off here today. This is not unexpected given the recent run-up, and current events (US government shut down, trade talks, etc). Note that QQQ (and TQQQ and QLD) are very close to the 13-day EMA. Can either:
1) Expect a bounce UP from 13-day EMA (which is $41.60 -- let's say $42, approx 161 on QQQ)
2) Break down below 13-day EMA, and possible retrace to 50% of recent lows (which was at QQQ 144, so 50% retracement = (144 + 166 ) / 2 = 155 QQQ. That's (7/162) = 4.3% below QQQ price now. That's 4.3 * 3 = 12.9% lower for TQQQ. That's approx $36.55 on TQQQ.
Let's wait another day or two to see what happens.