Does the base size of the planet matter for Ecumenopolis?

[KopiG]

So does it matter if I choose a size 12 or a size 25 planet for my Ecumenopolis? Will the max districts be affected or is it always 25?

 

[Tamwin5]

Max districts will be affected. A size 12 planet will still have 12 districts as an Ecumenopolis. That said, it's probably better to make a small or medium sized planet into an Ecumenopolis, atleast for your first one. Every Foundry Arcology and Industrial Arcology takes 60 minerals as upkeep; If you have 4 foundry and 4 Industrial, that will cost nearly 500 minerals to support them. Unless you have a Matter Decompressor, ouch. You simply won't need all the districts available. The other factor is that in order to create an Ecumenopolis, you first need to fill the planet with city districts. This can be done faster and cheaper on a smaller planet.

 

[Bouchart]

They'll have the same number of districts as the planet size (+1 if you finish the Expansion tree and +2 if you use the Mastery of Nature decision)

I wouldn't make an ecumenopolis based on the planet size. Instead, make a planet with very few resource districts into an ecumenopolis.