@Hufsa I've found a breeder of neos and caridina locally he said 25 percent a week water change. Which brings me to the next issue if your over dosing ferts somewhat you will need to dilute this to reset the tank is my understanding. I currently change 50 percent a week sometimes more as I've been moving the tank around at the moment. Should this be split into 25 percent twice a week 🤔 I don't want to spend 30 quid on some nice shrimp and kill them all!
I keep relatively high grade Blue Dream neocaridina, which I think is inherently more inbred and slightly more sensitive than regular cherries, but I could be wrong.
I have noticed mine do better with 25% water changes than 50%. But 50% changes daily back to back over several days is the worst for them, and I usually have some deaths then of the oldest individuals, which are less adaptable than the youngins.
Keep in mind that two 25% water changes is not the same as one 50%, even though it may seem that way. If you do two 25%, your second 25% change will be removing some of the new water from the first 25% change, leaving you with slightly less new water in total. This can be a positive or a negative, depending on what your goal with the water change was.
I would hold off on shrimp until your tank is fairly stable, and you have the majority of the usual growing pains out of the way. Meaning making sure you have actually stable CO2, there has been no misunderstanding with ferts and the dosing you are doing is right for your setup, gotten clear of the worst of the algae roadbumps which might require large frequent waterchanges, these kinds of things most people need to go through. Some people add shrimp pretty early to help with algae but if the goal is to make sure there are no chances of shrimp fatalities, I think it makes sense to wait, but thats just my personal opinion.
From my observations on the forum it seems I am among those who have more issues with water changes and shrimp than the majority reports, which is why I was wondering about the water hardness factor. Most of the forum members are from the UK after all, and have harder water than I do. If you also have harder water, and youre planning to keep regular red cherries, I would take their advice over mine, as their experiences would seem more applicable to you.