small pot. lower levels of light. Lower concentration of fertilizer to match. observe and adjust to any tox/def to dial that in just like any other context.
These will get rootbound, so you must plan the regeneration of the plant relative to future needs. How long does it take to clone and have a well-rooted plant that can give clones? Plan ahead.
1 gallon pot will be a bit larger than 30cm, but you just keep pruning it back to lowest growth tips and let it regrow.. Need to regenerate before it gets rootbound or the cuttings have a lower probabiity of success due to health of mother.
you can technically do this in perpetuity... though at some point issues do arrive with older plants and their clones.. not from cloning but from age. Hardened ovaries will ruin a harvest. it'll taste like shit.
As far as the anecdote about "dangers" of clones of clones.. that's retarded and not true. Take healthy cloens an it will be an exact copy of the mother. All clones and mothers are the same bioligical age and the same probability of some sort of genetic deterioration occurring at any time. Take healthy cuts and you get healthy clones. If the mother is 3 years old since it germinated, then the clones are also 3 year old plants as far as aging and the repercussions of aging are concerned.
I've regenerated mothers several times over and never had a problem. so the anecdotes about this topic clearly aren't a strong correlation to reality. just feelings of people that never tested the hypothesis.