In this video, Paul Hanson breaks down three very easy to use minor pentatonic scales that sound great over a minor (dorian) mode. Minor pentatonics are built by the using scale degrees 1, b3, 4, 5, b7. The pentatonic scales that he uses are built from the 1, 2, and 5. So in the key of G minor those scales are G minor pentatonic, A minor pentatonic, and D minor pentatonic. As you can hear, the different pentatonic scales sound different when played over the G minor, but they all work rather well as all the notes sit naturally inside the G dorian mode.
As with many things in music, there are at least two different ways to look at things. One way, taught in the Ramon Ricker Pentatonic Book, is not to consider major pentatonic and minor pentatonic as separate scales, but rather minor pentatonics ARE major pentatonics starting on a different note. For example the G minor pentatonic (G, Bb, C, D, F) is the same as the Bb pentatonic (Bb, C, D, F, G). So instead of using minor pentatonics based on the 1, 2, and 5, you can use major pentatonics based on the b3, 4, b7. It's the same thing, only you don't have to memorize 12 majors and minors, just the majors.
G major: G, A, B, C, D, E, F#, G
G minor (dorian): G, A, Bb, C, D, E, F, G
Major Pentatonic: 1, 2, 3, 5, 6
Minor Pentatonic: 1, b3, 4, 5, b7
3 'inside' Pentatonics to use when soloing in a dorian (m7) mode:
Minors OR Majors
1 (Gmin pent) b3 (Bb pent)
2 (Amin pent) 4 (C pent)
5 (Dmin pent) b7 (F pent)
Note how not only are the minor pentatonics the same as the major ones, all of the notes lie within the G dorian (F major) scale. This means no matter what you play, it will all sound inside. No note should sound out of place.
Gmin pent = G, Bb, C, D, F (G, A, Bb, C, D, E, F, G)
Bb pent = Bb, C, D, F, G
Amin pent = A, C, D, E, G (G, A, Bb, C, D, E, F, G)
C pent = C, D, E, G, A
Dmin pent = D, F, G, A, C (G, A, Bb, C, D, E, F, G)
F pent = F, G, A, C, D