Try to match your return pump flow rate to that of your skimmer pump intake flow rate. A too powerful return pump will only push water to bypass the skimmer and hence provide more nutrient to the main tank for algae to consume. For your tank size, skimmer option from Deltec is to use any model above APF851. For Reef Octopus, get the model above XP-2000. Do your research on this 2 skimmer eg cost of pump replacement if it decide to konk out, ease of maintenance and what not. Take your time.