According to Fedor's website via Wikipedia Aleks' tatoos:
Aleksander explained their meaning in his interview on Fedor’s official website.
Right arm: Cathedral with five domes: symbolizes five years of imprisonment.
Shoulders: Stars: Symbolize a "career criminal" or Vor v Zakone in Russian (english translation: thief in law).
Right shoulder: cobweb: Aleksander did not explain its meaning other than saying that contrary to what has been suggested by some, it does not have anything to do with the mafia. In Russian prisons, tattoos using this symbol typically denote drug addiction.
Left shoulder: Russian script.
Left forearm: Half cat’s head, half skull: “Homo homini lupus est.” Translated: Man is a wolf to his fellow-man.
Back: Grim Reaper holding a baby
Back: "Gott Mit Uns", meaning “God is with us” in German: for Aleksander, it’s a symbol of revival. This tattoo caused a significant controversy, since this slogan was written on belt buckles of German soldiers in the Second and Third Reich.
Knees: Stars: symbolize that the owner will never be brought to his knees.
Pirate tattoo: stands for article 167 of Russian Criminal Code: “armed robbery”.
“Fortune favors the bold” in German: self-explanatory.
A name on his lower abs (Maybe 'Marina'). Later covered by a tribal tattoo