Renko bricks for FX scalping: choosing a brick size

[Fairman]

ATR based brick sizes are an option on some platforms. The brick size is set by the ATR at the time the chart is built, so it adapts to volatility. The catch is that on some platforms the brick size is recalculated when you reload the chart, which changes all the historical bricks. That makes it hard to compare charts from different days or to backtest consistently. I'd use a fixed brick size and change it manually now and then, rather than letting it change automatically. A fixed size also keeps your screenshots and journal notes comparable over time.

[Fairman]

The two brick lag is the part that bothers me most about Renko on a scalping chart. With a 5 pip brick, a reversal only prints after price has moved 10 pips against you, so for a 6 pip target you're seeing the turn after the whole move has happened. I used it for a while for entries and kept arriving late with a stop that was too wide.

Using it as a second chart for trend, the way you describe, I think is its best use. When the last four or five bricks on a 4 pip ATR-based setting are all the same colour, I only look for longs on the time chart, and I ignore the shorts that look attractive.

On the sizing side, brick size also gives you a sensible stop idea. If a brick is 4 pips, a stop below the previous brick's low sits about 8 pips away, so for a 50 dollar risk I'd use roughly 0.6 lots. But since ATR-based bricks keep changing, that stop distance changes from day to day, which I find annoying.

Do you fix the brick size for a whole week, or let it update daily? And do you take the session context from a time chart sitting next to it?