Aquasoil I and II are both the same in terms of their water changing properties. I use I and II for tigers/crs and they both work fine.
It is best to go low-tech for shrimp because it's incredibly low maintenance and you won't have to do WCs if you make it a low-tech planted. Less WC = better for CRS in my opinion. Of course, that means you need to have zero nitrates all the time, thus allowing you to escape the burdens of a WC.
Why is doing less WC better for CRS (and shrimp in general)? For aquasoil users mainly, if your tap is 7.6 and your tank water is 6.8, doing a water change will basically cause a huge PH flux and will cause a lot of stress to the fragile CRS. I used to do a ton of WC because I thought I had to, even though my nitrates were at 0. I would find a dead CRS from each WC. So I stopped doing em all together and the deaths stopped occurring. Just remember, WCs are needed to remove nitrates. But if nitrates aren't even there, why do em?
All I do is top-off for my shrimp tanks since nitrates never go up due to plants.
The ammonia spike isn't even really a random spike. Aquasoil MUST be cycled before used inside tanks with fauna. It's as simple as that. Once the initial set-up is made, aquasoil will no longer make your ammonia jump. What's great about this soil in terms of cycling is that it leaks out its own ammonia, therefore, you don't have go add an ammonia source to cycle the tank. Just let it sit there with the filter on and you're set.
So anyway... CRS parameters...
Low PH soft water
70-74 temp
and... that's pretty much it.
Plant the tank with some moss and you're pretty much set.
