[CARE] When and How to do a water change for CRS?

My signal of changing water:
1) When I remember, I will randomly do at spare time around 2-4 days
2) Do regular TDS testing, like my normal tank water is TDS 288, when it high to 295~300. I will give it a water change.

Some breeder's *Stable tank can do 50% ~ 70% water change and the CRS flys around 20 mins will become normal. and that is good 50%-70% can take out many harmful elements for CRS. A regular 50% water change is necessary to give them a signal for them to molt.

Normally, I add water / Water change not very regularly (around 3 days) but with small amount (3 gallon)and a 50% water change weekly.

In my opinion, in a *Unstable Tank a large amount of water change seem make CRS nerve/death/with eggs may dump the eggs/ frys may disappear.

The water sources :
- at least drinking water TDS aroud 30 for my drinking water
- accumulate the GH to 5 before put into tank
A good water sources solve many unknown problem of CRS and its the most important element for CRS.

I also use the dipping method to avoid sudden change of pH/GH in the tank for this sensitive species - CRS.

*Stable tank = strong cycled tank, great biological filteration for large amont of waste, can hold higher population/colony, more canisters helps, More water also have more stability.
*Unstable tank = cycled tank, but may be under cycling period (for me, first stage 3 weeks (after amonia spike, ok to put in CRS), 2nd stage 3month(plants, water flea grow, water will look blackwater ..), bacteria is not growing large.