Thanks for posting the pics. First, if you're feeding so much at one time that food is going in the overflow, you're feeding too much at once. The key is feeding smaller portions several times a day (if you can). It should be a combo of flakes, pellets and quality frozen (not just mysis) like LRS or Rod's. NLS pellets and TDO are really good pellets (TDO being my preferred, as you don't need a lot to go a long way), Cool Green & Cool Mysis flakes are really good flakes (hand packed and cheap) and cover a lot of ground between the two. Also, I think you need more algae eating snails like trochus, astraea and turbos, nassarius are good at cleaning up leftover food, but you don't need a lot, as the bristle worms will be your best CUC in that regard. If you have a sump, then you can put an auto feeder in your sump's return section and use a small powerhead to keep the food in suspension until your return pump gets it, which is how I have mine set up, which works like a charm and keeps the clutter down. I'm a huge fan of mixing herbivores (fish-wise), one zebrasoma, one ctenochaetus (bristletooth) and one rabbitfish (foxface), as tank size allows. This combo covers a lot of ground with algae control.Well the fish looked stuffed all the time and are unable to eat everything I put in there. Once the pumps kick back on extra food is just going into filter socks. Not going to an automatic feeder and cutting up my $$$ lid. CUC is all small snails, Trochus x3, Conch x1, x25, Nassarius x10, Cerith x20, (assuming they're all still alive). 15 small fish, largest is 3" Foxface. Did the best I could on pics. As usual the HORRIBLE Mobius wasn't cooperating.
Bio media like marinepure will soak up nitrates quickly, but over time will slowly clog up. I think you can safely remove a few of these blocks, which will allow nutrients to rise a little. I think feeding a little more in smaller amounts and removing a couple blocks will help you out. Long term, slowly change your CUC ratio and add healthy herbivores (fish) to the mix. There's a lot to unpack here, but hopefully some of this will help you?