My personal favorite substrate for Neocaridina and certain types of Tiger shrimp is plain old sand or gravel which the shrimp love to sift through and forage for food, I prefer river sand because of its nice balanced color which suits aquariums.
To wash it all you have to do is place it in a bucket of water and stir it up with your hand, repeat this process and empty out the dirty water.You can also use pre-washed gravels like pea gravel but don’t ever pre-wash an active substrate it is not required
For soft water species, I prefer to use an active substrate that lowers the ph down to around a 6. This is important with Caridina species of shrimp because the lower you keep the ph around the more breeding success you will have and you will also get a higher survival rate among your young shrimp.
The way an active substrate work is through cation exchange which is common in acidic compounds, the soil naturally has a negatively charged property which removes positively charged Ions from the water, for us this does a few things, first, it lowers ph secondly it purifies the water.
You should also use a minimal depth of 3cm in all of your shrimp tanks this is because different bacteria have different needs and some of them are light sensitive, take aerobic bacteria, for example, they require little to no water movement and some species require complete darkness.
The only downfall of an active substrate is the need to replace them when they become exhausted, You will know when this happens because your shrimp will stop breeding as your pH starts to climb.
I personally like Akadama which is a cheap rock hard bonsai soil meant for terrestrial plants. However because it is so hard it is suitable for aquarium use, it also gradually lowers the Ph down to roughly a pH of 5-5 to 6.5.
I have recorded this substrate lasting for 3 years and I do 25% water changes every week in my tanks, its only flaw is its color which can look orange at times. Substrate choice is of pure preference so do your research and ask questions in forums.
I am assuming that you will have bought a tank and have an interest in shrimp before buying my shrimp guide but if you have not we shall go over the basics of tank setup.