From reading that is an example of too big of a skimmer (fish load or tank size).
That can also happen to a poorly tuned skimmer too though....for example, a crusty air-intake tube, sump water too low, or even inadequate cleaning frequency can have at least a similar effect.
Have tried adjusting the drain to raise up the level of the foam? I assume the air-intake on the pump is wide-open?
If those are true and you just think it's the bio-load, then maybe a new skimmer is called for.
It obviously depends on you and your system, but I tend to recommend AquaC and Tunze skimmers these days. I own and like both quite a bit.
I'm not a needlewheel "believer" so I don't hesitate to recommend the older-style AquaC's....they work really well and have a lot to recommend them.
However, I'm not a needlewheel "deny-er" either, so I also really like (and run) Tunze's skimmers. They do not engage in the gimmickry that most other makers engage in and they have some really unique and useful features.
For a lightly stocked system around 300 gallons, I'd say to check out these two:
- Tunze 9415 - still a bit oversized for your system, but should be more than flexible enough to be dialed in. The 9410 is a great bargain at $320, but I think it might be too small.
- AquaC I'd probably try the EV-240 first and consider that it may need some small size-upgrades like the bigger 1" inlet and a slightly oversized (per their recommendations) pump. The EV-400 could work too, and it meets your size range, but it's so big (almost three feet) I'd be a little worried you could end up in the same barely-skimming boat. AquaC's are easier to find used than a lot of skimmers, so if you happen on a 400 for a great price, it could be worth trying anyway. They also do custom skimmers, so they could make you something that's a better fit for your cabinet (like a shorter EV400 or EV1000) if none of these seems quite right.
If you have a local dealer that will let you try and, if needed, exchange...start with the smaller recommendations in every case, and work your way up.
You could also look at this as an opportunity to feed more (mostly for the corals) instead of changing skimmers. :) :)