2 weeks of scrubbing with my ATS box

[Fishuntbike]

2 weeks of scrubbing with my ATS box shows a bald spot in the middle which is common when using spiral bulb. I will keep addding Kent iron + manganese and see what it will bring next week, otherwise I have to make adjustments to water flow, bulb wattage, light On duration etc...to have a screen fully covered with green turf.

[SantaMonica]

Correct. Last resort is less hour ON, or worse, smaller bulbs, since that reduces the total filtering. Yours is a pretty strong burn spot though, so getting it to fill in might take a combination of things.

[Fishuntbike]

thanks for the advice, I will see next week on what adjustment I can do