I've just upgraded the filter in my Aqua Essentials 60cm opti-white - again. It's a Superfish Pro 4 external with max. rated flow of 1550lph. It just about squeezed in the cabinet alongside my 6-way extension lead and 2Kg FE CO2 system. Outflow is through an Aquatic Magic glass lily pipe and the circulation characteristics are superb. All the plants sway gently throughout the water column. Inlet is a regular JBL plastic thing as I broke my glass one. I'm considering a 17mm ADA set but at almost Â£200... I may go a bit crazy at the TGM/ADA day! I've also fitted the brand new Arcadia OT2 luminaire. Look out for a PFK blog soon on this tank complete with photos etc.