After a few years and hundreds of shrimp I stopped cleaning the bottom altogether. But if I were going to I would fasten a brine shrimp net over the intake to keep shrimp out and catch some of the small debris.
I use a turkey baster from the dollar store. Also I can’t quite see it but if you haven’t already covered your intake you should put a sponge over it so they don’t get sucked up into the filter.
When U stir up the bottom, it suspends more nitrates in the water causing a spike. I have a high light setup where the plants can gobble it up but with a low light system it makes it more difficult. Doing small bits on a regular basis would stir up less debris and doing a water change after would help, but overall, ur going to have to do everything in small steps with ur setup.
Airline tubing instead of a gravel vac. Get a long piece, maybe 5-8 feet (probably the whole package), and start a siphon into a bucket. Detail clean with one hand holding the tube over mulmy areas. keep the other hand holding the tubing and ready to pinch the line if you suck a shrimplet up. Then just wag it around a little so it swims back out of the tubing.
blakeuk 
After a few years and hundreds of shrimp I stopped cleaning the bottom altogether. But if I were going to I would fasten a brine shrimp net over the intake to keep shrimp out and catch some of the small debris.
I use a turkey baster from the dollar store. Also I can’t quite see it but if you haven’t already covered your intake you should put a sponge over it so they don’t get sucked up into the filter.
When U stir up the bottom, it suspends more nitrates in the water causing a spike. I have a high light setup where the plants can gobble it up but with a low light system it makes it more difficult. Doing small bits on a regular basis would stir up less debris and doing a water change after would help, but overall, ur going to have to do everything in small steps with ur setup.
De skrimps dey do dah clean. 😉
Them and the nerites.
Detail cleaning and water changes are my go to.
Airline tubing instead of a gravel vac. Get a long piece, maybe 5-8 feet (probably the whole package), and start a siphon into a bucket. Detail clean with one hand holding the tube over mulmy areas. keep the other hand holding the tubing and ready to pinch the line if you suck a shrimplet up. Then just wag it around a little so it swims back out of the tubing.
I’ll also do this with my larger tanks.
You don’t clean sand at the bottom of your tank. You leave it alone.