Leveling a tank can be a challenge. The amount of challenge will depend a lot on the type of tank you play. Some tanks have more DPS (Damage Per Second) then others. My tanks tend to be very strong tanks with very little to no DPS :P. The lack of DPS on many tank builds require that you level with a group.
One way to deal with this issue is to use an iconic race for you build. That way you start at level 15 and bypass a few of the growing pains. Still a challenge though unless you have a dedicated group.
One way I have dealt with this is to level my tank as an Inquisitive. I choose the levels/classes same as I would for my tank, but pick ranged feats as listed below.
Then when I get to level 30 (could do sooner if you wish) I do a lesser reincarnation to adjust the feats to those I need for a tank. Now in the case of my tank, I also like to run him as a PDK so I also get to start the inquisitive at level 15. I have done this 3 or 4 times now and I like the way it works for me.
Here is a link to the actual tank build choices
http://malkier.xyz/community/tanks/bologrubb-tank/#post-4585
Tank leveling ranged
12/4/4 Paladin/Fighter/Artificer
Lawful Good Purple Dragon Knight
Level Order
1. Fighter 6. Paladin 11. Artificer 16. Paladin
2. Artificer 7. Paladin 12. Paladin 17. Paladin
3. Fighter 8. Fighter 13. Paladin 18. Paladin
4. Paladin 9. Fighter 14. Paladin 19. Paladin
5. Artificer 10. Artificer 15. Paladin 20. Paladin
Stats
36pt Tome Level Up
---- ---- --------
Strength 8 +7 4: INT
Dexterity 16 +7 8: INT
Constitution 16 +7 12: INT
Intelligence 18 +7 16: INT
Wisdom 8 +7 20: INT
Charisma 8 +7 24: INT
28: INT
Skills
F A F P A P P F F A A P P P P P P P P P
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
------------------------------------------------------------
Disable 5 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 23
Open Lo 3 1 1 8 1 1 1 1 2 1 1 1 1 23
Search 2 2 1 1 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 23
Spot 2 1 1 4 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 23
UMD 2 3 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 23
Diplo 2 4 1 1 1 1 2 2 2 3 19
Jump 4 4
Heal 1 1 1 3
Balance 2 2
Tumble 2 2
------------------------------------------------------------
28 10 8 9 11 9 9 10 10 12 12 11 11 11 11 12 12 12 12 13
Feats
1 : Point Blank Shot
1 PDK : Precise Shot
1 Fighter: Rapid Shot
3 : Precision
3 Fighter: Weapon Focus: Ranged
6 : Toughness
9 : Dodge
9 Fighter: Power Critical
11 Arti : Improved Critical: Ranged
12 : Improved Precise Shot
15 : Mobility
18 : Shot on the Run
21 Epic : Combat Archery
24 Epic : Overwhelming Critical
26 Destiny: Holy Strike
27 Epic : Blinding Speed
28 Destiny: Doubleshot
29 Destiny: Harbinger of Chaos
30 Epic : Epic Damage Reduction
30 Legend : Scion of: Arborea
4 Deity : Follower of: Silvanus
14 Deity : Blessing of Silvanus
Spells
Paladin
1. Protection from Evil (12), Virtue (14)
2. Angelskin (16), Resist Energy (18)
3. Magic Circle Against Evil (19), Cure Moderate Wounds (20)
Artificer
1. Resistance (2), Ablative Armor (2), Master's Touch (5)
2. Admixture: Cure Moderate Wounds (10), Lucky Cape (11)
Enhancements (Spent: 80+5r +0u / Max: 80+5r +0u AP)
Inquisitive (42 AP)
• Inquisitive, Hit the Streets, Mind Like Iron, True Seeing, Undaunted, Master Inquisitive
1. Dual Shooter, Eye for Accuracy III, Law on your Side, Inquisitive Skills III
2. Crossbow Adept, Observation, Improved Law
3. Crossbow Adept, What First?: Shoot First, Intelligence
4. Crossbow Adept, What Later?: Ask Questions Later, Inquisition Style: Martial Inquisition, Greater Law, Intelligence
5. No Holds Barred, Inquisitor's Path: Jaded, Diplomatic Immunity
Battle Engineer (24 AP)
• Battle Engineer, Infused Weapons
1. Crossbow Training, Field Engineer III
2. Crossbow Training, Wracking Shot III, Extra Action Boost III
3. Crossbow Training, Intelligence
4. Intelligence
Purple Dragon Knight (19 AP)
• Damage Boost, Intelligence
1. Improved Recovery, Don't Count Me Out III
2. Sniper III
3. Improved Recovery, Heroism
4. Improved Recovery, Greater Heroism