Question: What Russian rock group formed in Leningrad has a bassist who also performed with Avvgust?

Context paragraphs:
Leningrad (band): Leningrad (Russian: Ленинград ), also known as Gruppirovka Leningrad (Russian: Группировка "Ленинград" ) and Bandformirovanie Leningrad (Russian: Бандформирование "Ленинград" ), is a popular Russian rock band from Saint Petersburg (formerly Leningrad), led by Sergey "Shnur" Shnurov.

Aquarium (band): Aquarium or Akvarium (Russian: Аква́риум ; often stylized as Åквариум) is a Russian rock group formed in Leningrad (now Saint Petersburg, Russia) in 1972.  The band had many member changes over its 40-year history, and at the end the only remaining original member was lead singer and founder Boris Grebenshikov.  Former band members have included Anatoly Gunitsky, Dyusha Romanov, Sergey Kuryokhin, and Vsevolod Gackel.

Alexander Titov (rock musician): Alexander Valentinovich Titov (Russian: Алекса́ндр Валенти́нович Тито́в ; born 18 July 1957 in Leningrad) is a Russian rock musician, known for his role as bassist of the band Aquarium, position previously held by Fan (Michael Feinstein-Vasiliev).  He has also performed with the bands Avgust, Pop-Mekhanika, and Kino.

Red Wave: Red Wave: 4 Underground Bands from the Soviet Union was a split double album released in 1986 and featuring Russian rock bands Aquarium, Kino, Alisa, and Strannye Igry (Strange Games), all from Leningrad.  It was the first release of Russian rock music into the United States.

Leningrad Cowboys Meet Moses: Leningrad Cowboys Meet Moses is a 1994 film directed by Aki Kaurismäki.  It is a sequel to the popular 1989 film "Leningrad Cowboys Go America" that introduced the fictional Russian rock band Leningrad Cowboys which, subsequently, became a notable real life rock band in Finland.

Alexander Vasilyev (musician): Alexander Georgievich Vasilyev (Russian: Александр Гeopгиeвич Васильев ; born July 15, 1969 in Leningrad) is a singer, songwriter, and frontman of the Russian rock group "Splean".  Vasilyev also released one solo album, and sometimes assisted other groups and artists.

Piknik: Piknik (Picnic, Russian: Пикни́к ) is a Russian rock band known for its unique style which is a mixture of art rock, progressive rock and original Russian rock.  The band was formed in 1978 in Leningrad by Sergey Omelnichenko, Evgeny Voloschuk, Aleksey Dobychin and Edmund Shklyarskiy.  Piknik is considered to be one of the "classic" Russian rock bands.  Originated from the classic rock with huge influence of Jethro Tull and Led Zeppelin, its music progressed into its own style with using symphonic and exotic folk instruments.  Also Piknik is considered sometimes to be the first Russian gothic rock band due to its specific sound, stage performances and dark lyrics.

N.E.P.: N.E.P. (Russian: "Н.Э.П." )  is a Russian rock band formed in 1988 in Saint Petersburg, then Leningrad, and widely credited as a legend of Russian rock music and classics of Russian rock, according to the biggest national mainstream rock radio.

Leningrad Rock Club: The Leningrad Rock Club (Russian: Ленинградский рок-клуб ) was a historic music venue of the 1980s in Leningrad, situated on Rubinstein Street in the city center.  Opened in 1981 and overseen by the KGB, it became the first legal rock music venue in Leningrad.  Overall, it was the largest rock scene in the Soviet Union, which featured such bands as Televizor, Kino, Alisa, Aquarium, Zoopark, Piknik, Automatic Satisfiers, DDT, NEP, Grazhdanskaya Oborona (formally), and became an important influence on the Russian rock.

Orgia Pravednikov: Orgia Pravednikov (Russian: "Оргия Праведников" , translated as 'Orgy of The Righteous') is a Russian rock group formed in 1999.  The peculiar sound of the band arises from the combination of acoustic (flute and acoustic guitar) and electric (drums, electric guitar and bass guitar) sessions.

Supporting paragraphs: Alexander Titov (rock musician) Aquarium (band)
Answer: Aquarium