I didn't know this until today (what a noob
) so I've been sending only the amount of cargoes needed to loot (actually transport) half of all the res, this does work in 90% of the cases, but not always. After this attack (https://gempire.rpg-board.net/t986-crusygempire-vs-shibiz-fubar-nuke-and-farm) I decided to read up in the wiki on this, because I did not get all the res I was expecting.
So there is always a theoretic plunder, which is always half of all the resources on the planet:
For example the theoretic plunder could be:
900'000 & 200'000 & 100'000'000
And the transports that I have supposed I would need would be 48 Large Cargoes, which could hold 1'200'000 res.
BUT I found out today there is a rule about how the res is loaded onto the ships.
1. A max of 1/3 of the ships capacity is filled with metal. -->400'000
2. 1/2 of the leftover capacity gets loaded with Crystal. (800k/2 = 400k) but only 200k can be looted so its -->200'000.
3. The rest is filled with the Deut --> 100'000
4. If there is still capacity (1200 - 700 = 500) half of that capacity is loaded with metal. --> 250'000
5. Now the rest is filled with Crystal if there is still some left.
!! Result: the ships go home without loading all the metal theoretically available, 250'000 stay on the planet !!
This means if there is lots of metal to be looted you need to send more ships to collect it all. Some of them will stay empty, but you can collect the full theoretic plunder in a single attack.
Here is the link to the wiki article:
http://ogame.wikia.com/wiki/PlunderI hope I could help some of the other noobs that did not know this be even more effective with thier farming raids. By the way speedsim does correctly give you the amount of ships needed.