Looks like you have a massive nutrient imbalance and lack of proper mechanical/biological export in place. To further make it worse, maybe you’ve had quite a bit a of cleanup crew like snails that have perished in the tank further contributing to the nutrient load. Chemiclean isn’t gonna fix this
I would do the following:
1.25% water change and siphon out as much dinos as possible(off rocks and sand)Remove all empty shells, any detritus, suck out bubble algae etc.
2. Figure out a way to add additional water polishing filtration equipment. A small uv, ozone, a larger skimmer(or make sure the one you have is actually working correctly, and a way to skim the surface of your water. If you don’t have some sort of mechanical filter like a sump, canister, hang on the back, something…get one set up. You need a place to run filter pads to pick up any particulate floating around. This way you can rapidly remove all the stuff circulating around.
3. Turn off your light for a couple days and when you turn it on run it minimally if you must. Basically you need to the biological to catch up with the nutrient load and by keeping the light off, you will decrease the Dino population.
4. After a week, I’d do another water change and continue on doing this weekly until the problem dissipates.
Without all the particulars of your tank, this is just general advice