White water / detritus issue.

[AZdogpatch06]

I'm not sure if it's the lighting or suspended substrate, but I can't seem to get the white water effect to go away. Also can't figure out how to properly clean my sand bed. I use a syphon that I have for my freshwater tank but I always seem to suck up a few handfuls of sand. Afterwards, I can't figure out how to get it clean to put it back in the tank! All the particles of waste just stay in the sand. How often should I feed? Perhaps that's causing the excess detritus on the sand bed? Just did a large 30 percent water change and that helped a little. Note I have a 25 gallon tank so I replaced roughly 7 gallons. I'm running a biocube air driven skimmer and a hob filter with filter floss (it's a foam pad actually) activated carbon, and bio pellets. It is an aquaclear 50. Inhabitants: 1 clown. 1 Indigo dotty back. 2 peppermint shrimp. 2 emerald crabs. 2 turbo snails. And a handful of hitch hiker hermit crabs and bristle worms. Oh, and some Kenya tree and polyp coral. I'm only 6 months into the saltwater world, so any help would be great!

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[Sniperhank]

Don't clean your sandbed. The only time that you want to disturb it at all is if you need to suck up a cyano outbreak...which then you want to suck the cyano up, not the sand.
Carbon should be polishing the water for you, basically. Are you sure the 'white' effect isn't reflection from the white arches and such you have in your tank? That is all you can see in the picture.
In terms of feeding, you should feed sparingly. I feed my 55 reef tank half a cube of mysis every 3 days. You don't want excess food floating around. What you put into the tank you need to remove. This is one reason we do water changes, to take the nitrate/phosphates out. The media you can run will absorb some of this, but not all.

 

[Animal-Chin]

I see a biocube skimmer in the tank, it could be releasing microbubles into your tank. Try turning it off for an hour, does the cloudy clear up?