Simple maths for earning strategies. There are 1440 minutes in a day.
My earth habitat holds 3 level 20 panlong dragons and they pull in 540 coins each per minute, making that one habitat yield 1620 coins per minute. In 52 minutes my habitat has earned me 74,800 coins. The total earnings from my earth habitat with 3 panlong dragons is worth 2,332,800 coins per day if I check in as soon as my earth habitat reaches its cap of 75,000 coins.
My large moon habitat holds 3 blue moon dragons and they pull in 316 coins each per minute making that one habitat yield 948 coins per minute. The same goes for my large sun habitat with 3 solstice dragons. The total earnings from my large moon/sun habitat with these 3 dragons is worth only 1,365,120 coins per day. That's a shortfall of 967,680 coins in comparison to one earth habitat panlong level 20 dragons earning 2,332,800 coins per day.
So, it comes down to how frequently you sweep for coins. The earth habitat caps at 75,000 coins. The large sun and moon caps at 1,250,000.
So, if I get 8 hours sleep and my earth habitat only earns 75,000 I am missing out on 428 minutes of earning and that equates to a loss of 616,320 coins.
So, if I sweep every 52 minutes (taking into account my loss during sleep time)
I would be in front by 466,480 coins per day by having panlong earth habitats compared to my large sun/moon habitats. However, I can't sweep that time frame every day due to work and family life, so for me - the large sun and moon habitats work better. Simple maths really! Hope that clears up the confusion!
Just love the game!

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