Some claim yes some said no. As I said before every tank is unique due to setup, size etc.
Anubias poison basic is when the stem/leaf is damaged/trimmed the sap that leak is poisonous to shrimps.
So is upto you to decide. For me I don't like anubias and I take safe better then sorry path esp if the tank is full of expensive shrimps.
One things about plants in tank with shrimps is that you must be careful in adding new plants , alot of plants is grow emersed in farm and be spray with pesticides and fertilizers that are fatal to shrimps.  Any new plants need to know the source and be quarantine.  If buying from direct seller, ask them it is safe for shrimp. If from shop better test the plants in a bucket with one shrimp first before introduce in your tank else you risk wipe your whole colony.
Actived carbon can remove fert and pesticides.  Put them in the filter of the quarantine tank.
Fyi. We normally wont add in any new plants in established shrimp tank.

Can just give a basic guideline as parameters vary for different type crystal shrimp.
Ph 6.2 - 6.6
GH 4-6
KH 0-2
Tds 100-150

i check TDS more often, as too high TDS in water if it doesn't come from mineral addtives/rock , it reflect pullution in the water.
Sera test kit is ok , i'm using Sera GH tester , just take sometime to read the instruction manual.

Bacteria need to build up itself in your tank, it take time, to speed it up, you can add bacteria water and additives to promote bacteria growth, ample of oxygen in water during initial cycling will help a lot.

Some filter media like ADA bio rio and Biohome plus come with added bacteria in dormant state.

shrimp soil from benibachi , borneowild  or plant soil from ADA - new amazonia soil.

I heard this opae ula shrimp has a life span of 20 years?!  omg

for opae ula ?
opae ula need brackish water(half salinity of marine water at 1.012-1.016)
use RO or distilled water to make the brackish water , the won't survive in freshwater.

use mosura mineral plus , also can use benibachi emergency water.

First -Brand , second - ingredients , all 3 the will increase TDS and GH. How much and how much to use and how fast the effect vary on each type.
Third - price different alot with benibachi the most expensive , then mosura follow by Up Aqua.

But come to think of it , if anyone can afford a rm70 or above for one bee shrimps , these product price are just a tad of it.
If you want fast and also proven safe record on increase RO water tds/gh , go for mosura.
Benibachi will cost more if you on budget.

To buy
Mosura - try aquashop in lelong
Benibachi - benibachi reseller in malaysia , try search facebook for details.
Up aqua - some LFS in KL stock them. last saw them in fish depot and 88 petsmart.

I wonder how often do you guys vacuum your substrates to clean off the built up debris? is it necessary to do it often if you have CRS?

Lot of possibilities. 
-tank not cycled.
-lack of o2 -> temperature high > 28c, too much co2.
-ph , tds and gh not ideal. Ph around 6.2-6.6(6.4 ideal)  tds 120-150 and gh 4-5.
-water high nitrate > 40ppm , overfeeding? (Feed everyday?)
-water flow too fast -Crs actually gripping on soil inorder to move?

Nitrate is NO3, unless you got lot of crs(> 100tail in an 2 ft) , you no need to feed everyday, once every 2 or 3 days with small pcs is enough,
too much food esp these high in protein do more harm then good. Your tank have natural food for them (biofilm/algae).
GH for crs , stay at GH4-6 enough , don't increase GH more than 0.5 in 24hrs when shrimp already in tank , this will shock them.

i'm using shrimp soil buffer down the ph, my tap water is ph7.6, with soil , it stay at ph6.4.
There is liquid tester for GH and KH as well.

what soil you using ?
snail , ppl put nerite , ramshorn snail with shrimps.
Yes , i change water 10% every week, PH never change from 6.4.
soil buffer not refer to soil thickness , it refer soil as a medium that can hold and lower/up the ph. for exp. acidic soil like ADA amazonia/Benibachi shrimp soil will lower PH , coral sand will increase/up PH.

ADA soil, at least 2yrs, benibachi around 1-2yrs depend on your filter system.

Nope, if your filter system is powerful like using high powered canister filter , the soil properties will be filter out faster and depleted resulting
in buffering power depleted faster.
for example , in one of my tank , i use UGF combine with canister filter , the shrimp soil i use the buffering power only last 1yrs++,
where else another tank with UGF & sponge filter only, it last 2yrs++.

Fish, follow the rule, if shrimplet size fit the fish mouth, it will eat them. So get the smallest fish you can, like guppy/swordtail baby.

Yes, sign of soil expiry is losing buffering power which mean, ph, gh and tds will run and fluctuate with every water change.
my ugf is air pump driven.
That why the higher grade of crs you keep the more you to be precise with your setup.
even basic setup for crs cant runaway from maintaining proper ph, gh , tds and temperature. This is one of the main reason why crs is never a beginner shrimp.