Hello Logicalmind,
Welcome to TFP!
Glad to have you here.
The 1st thing that comes to mind since you can't filter it out is to SLAM your pool. This stands for "Shock Level and Maintain". You can read about it in pool school, see my sig.
This will begin to break down that Goo, allowing your filter and vac to do their job.
You'll need one of our recommended test kits to do this, as well as to continue to maintain your pool the TFP way. See my sig link titled "TF100 Test Kit" for a comparison.
We do not recommend the use of flocculant as a regular treatment and using the TFP method is completely unnecessary. I have an Intex pool and last year with the tiny pump and filter in my sig, I kept a sparkle clean pool. Nothing but bleach and muratic acid.
We do use floc on occasion to help people clear their swamps and the like, but It's not a regular thing and only in special cases.
In normal daily maintenance, floc should
NEVER be necessary.
TFP isn't so much about using specific chemicals, as it is understanding and educating yourself as to what those chemicals and others do and how. Thus the effect on your pool and your pocketbook. This happens through use of a proper test kit, pool school and this forum and its collective knowledge and experience.
Lastly, if you want to try something else, disconnect.the suction side simmer hose, weigh it down on the bottom of the pool and leave it there. Take the return and try to point it high with a pvc elbow that'll fit in its hole. I found one at HD for this purpose, one end just press fits in to the return.
This should grab that Goo with minimal disturbance. As for cleaning the filter.... yeah, you'll have to do that . Aaallllooootttt!
Try 2 nylons from those cheap'o 29c clear eggs @ Walmart. Use both, one toe over each end, drawn tight and evenly distributed over the length of the filter pleats of the cartridge with no wrinkles. This should be used anyway, just makes life easier with those Intex undersized filters. It adds additional surface area and a finer Micron filter. Also easier to hose off as the bugs and bits don't get hurried inside the filter where they're hard to hose out.
Don't bother with this on the skimmer, doesn't work due to water bypass of the basket since it's non-sealed.