Originally Posted by lovemyreef
I also have around 1800 gph
flowing on the tank.
Besides possibly overfeeding this flow is your second issue. 30x-50x times turnover is recommended for reef tanks 1800gph mean that in a 125g you only have 14.4x turnover. This low flow results in a large number of dead spots or areas of low flow and causes detritus and organic matter to settle and rot. Flow will prevent things from settling so it can be filtered or removed through skimming. Flow is everything in a reef tank and ultimately a major factor in your algae problem.
For comparison i have approx 1800gph total on my 29g standard, yes i said 29g. To have the recommended 30-50x turnover in your 125g you need 3,750-6,250gph flow. Also in most situations this is not including return flows etc.
Hope that helps.
29g Mixed Reef, 150w 14k Phoenix MH w/ Moonlights, Reef Octopus BH1000 HOB Skimmer, Ecotech Vortech MP10es, ReefKeeper Lite (Plus), PH Probe, Temp Probe, ATO, Carbon/GFO Reactor.