--- bloom.sgml.old	2018-07-24 16:40:23.000000000 +0300
+++ bloom.sgml	2018-10-15 00:11:01.000000000 +0300
@@ -51,8 +51,8 @@
     <term><literal>length</literal></term>
     <listitem>
      <para>
-      Length of each signature (index entry) in bits. The default
-      is <literal>80</literal> bits and maximum is <literal>4096</literal>.
+      Length of each signature (index entry) in bits, it is rounded up to the nearest 
+      multiple of 16. The default is <literal>80</literal> bits and maximum is <literal>4096</literal>.
      </para>
     </listitem>
    </varlistentry>
@@ -242,6 +242,16 @@
       operations in the future.
      </para>
     </listitem>
+
+    <listitem>
+     <para>
+       Bloom AM doesn't supports <literal>unique</literal> indexes.
+    </listitem>
+
+    <listitem>
+     <para>
+       Bloom AM doesn't supports <literal>NULL</literal> values.
+    </listitem>
    </itemizedlist>
   </para>
  </sect2>