Have you changed your fert schedule at all ?
ATM I am using only iron, and flourish @ half recommended dosage, and at water change only. I find any more than that and I get an influx of algae. - I would say it is attributed to the high nutrient content of the Aquasoil. I'm sure in time, once the ferts are depleted from the soil, I will have to increase the dosage.
- but hey, if the plants are full of colour, healthy and growing fast, I need not do any more than what is working. Good lighting and co2 ATM, with minimal ferts is dong the trick - so far anyhow.