Not sure what you mean with "removing particles older than 0".
There's 2 operators that I am using most of the time, when I have a need for a referenced Tyflow
1) Birth Flow
(it just makes the static particles, from the first flow (you can choose from whatever frame you want).
2) Flow update
(it copy animations (movement) from the first flow paticles).
To save time, you can simply right click in the empty space of the first flow, then select Preset Flow - and then - Simple reference Tyflow.
And Tyflow will automatically create you a copy of Tyflow with Birth Flow and Flow Update referencing the first Flow
(very handy, if you ask me, and I use it all the time
).
So, after you have referenced Tyflow, you can do with it whatever you want.
Delete particles, add new ones, change their shape (but you have to disable shape in Birthflow and Flow update ops)...
And yeah.. you should be able to delete them by age too (if that's what you're asking).
Hope this helps.
There's 2 operators that I am using most of the time, when I have a need for a referenced Tyflow
1) Birth Flow
(it just makes the static particles, from the first flow (you can choose from whatever frame you want).
2) Flow update
(it copy animations (movement) from the first flow paticles).
To save time, you can simply right click in the empty space of the first flow, then select Preset Flow - and then - Simple reference Tyflow.
And Tyflow will automatically create you a copy of Tyflow with Birth Flow and Flow Update referencing the first Flow
(very handy, if you ask me, and I use it all the time
). So, after you have referenced Tyflow, you can do with it whatever you want.
Delete particles, add new ones, change their shape (but you have to disable shape in Birthflow and Flow update ops)...
And yeah.. you should be able to delete them by age too (if that's what you're asking).
Hope this helps.