Here are the pictures who can maybe explain better what I talking about.
Here is the bacterial bloom created second day after I moved my diy reactor to this aquarium who had 50 mg/lit nitrates
here is the skimmer picture
That diy reactor made similar bacterial bloom in previous aquarium few days after modification. Until modification he work for months without bacterial explosion, I think I do something what made him bacterial machine but dont know exactly what,lol.