Little update, I've bought a RO system. I'm transitioning the tank water to 100% RO, right now I'm using MgSO4 and CaSO4, 0 KH.
Last week I did 50% WC, GH is 7 (still 50% ro and 50% tap) and KH is 3.
The TDS from Ro unit is ~20ppm (scale500), I add GH 5 (3:1 ratio), I don't add any alkalinity due to aquasoil. GH 5 should give me around 110-130ppm of tds (+20ppm from RO)
This way I should be able to have CRS. But now I have some doubts.
The tank has cpd, ember tetra, otos and pygmy.
- embers (10) swim mid to top, rarely see them at the bottom. Should be safe
- cpd (8) are always at substrate level, they eat from the substrate
- pygmy (6) are safe, they ignore everything in the tank
The tank is 90g 110x50x60h, Dutch style inspired.
I want a clean up crew made by shrimp, I have 1 amano, I plan to add more friend to this guy (maybe 9 more, so 10 in total for 90g of water)
But what about CRS? Would they be just a snack for cpd or I'll be able to have a colony?
Photo of the tank below.
I would like to add Rummynose but they are hunters, and very active, maybe aren't even less safe for CRS.