Thank you very much for reading this.
I am 25 days into a fishless cycle of a 450 litre Juwel Vision 450 bow fronted converted to marine with a 90 litre sump tank, 2 x 12" air walls, 1 x 4" air disc, 2 x 3000 l/p/h powerheads, 1 x 1500 l/p/h sump return pump, sump contains 3 chambers...