What is wrong with my UAS

[handy77]

Hi. I need your input on my DIY UAS. I used 5 LED 3watt 660nm as can be seen in the attachment. This UAS has been running for about 4 weeks. What happened is the algae is not growing in the net but in glass while the net only gets brownish without any algae. Please, appreciate your advice.

[SantaMonica]

Welcome from Indonesia.

It is normal to start on the glass first. After the screen gets thick, it will rub the growth off of the glass.