That's why are asked if there was still any diatoms. Just odd its worse with the light on.
Your friend is correct. You do have a very low bioload but you have also been feeding. I suppose if every scrap is being consumed you may have some bacteria die off but if the bacteria was dying at that rate you would have no doubt seen a spike due to the death of the bacteria
So how much rubble are you using? There is no reason should have to have a skimmer at this point but it can't hurt to add one.
oh sorry bud, nope, no diatoms to speak off. some GHA (very few strands) as well as some other wavy stringy stuff and a tad bit of green.
no spike witnessed by my testing, but to be honest i only do it once a week now as nothing has changed for me to do more.
going monday to pick up some rubble from him. he said he can give me a few pounds and some sand if i want it.