Delete record from table if certain fields are empty upon closing a Form

I am trying to get a button to close a Form and at the same time delete records on a table where certain fields are empty. I have this on the Form:

Private Sub cmdClose_Click()
Dim sql As String

sql = "DELETE *" _
     & " FROM [AlimentoporTanque]" _
     & " WHERE IsNull(Tanques) OR IsEmpty(Tanques) OR Tanques = "" OR Tanques = 0" _
     & " OR IsNull(Alimento) OR IsEmpty(Alimento) OR Alimento = "" OR Alimento = 0"
CurrentDb.Execute sql

DoCmd.Close , ""
End Sub

AlimentoporTanque is the Table’s name and Tanques and Alimento the fields that should not be empty. When I click on the button I get following MsbBox popping up:

What am I doing wrong? How do I get this running? Thanks in advance.

Answer

I got it working. This is the working code:

Private Sub cmdClose_Click()
Dim sql As String

sql = "DELETE *" _
     & " FROM [AlimentoporTanque]" _
     & " WHERE Tanques is Null" _
     & " OR Alimento is Null"

CurrentDb.Execute (sql)
DoCmd.Close , ""
End Sub