Every one just breed sea dragon (lvl 10) on the left and terra dragon on the right (lvl 10) most of the time either you'll get waterfall dragon or mud dragon. Keep breeding both you'll get it. I got it too 19 hrs 59 min :)
Never got Plankton when you play on Ipad (I tried for 50 times :)). Try to breed Plankton on browese (firefox), just combine terra and water. I try for 5 or 6 times to get it. It's easy because when you miss, you just have to wait for 1 min to try again.
Guys & girls, if you get it on your first try, it's called luck. Not 100% certainty. There is no such thing as a 100% certainty, not in this life, except that we are all defintely going to die one day.
If at first you don't get it, check your formula. Check your dragons levels. If it is all as it should be, try again. Some dragons are harder to get than others, so you may have to try several times (or even 50 times) before you finally get the one you want.
You can get plankton by breeding a sea lv 10 and a terra lv 10 several time. If u fail the breeding time is 1 minute and sell the egg. If the time of breeding is 20h (from the beginning), u know u success
I am not sure, but I think that you would have a much better chance to get it by breeding mud(4lvl) and another mud(4lvl). The rate value would be 46, so that means that you would have 33.33% chance to get it. And it is not possible to get more %. The combination that you are using has rate value of 147, that means that the chance to get plankton is only 10%. There is more info here: http://dragoncity.wikia.com/wiki/Breeding/Rate_Value
Keep in mind that when I wrote this, I forgot that you need lvl10 parents :)
It is worth mentioning that a lot of this information is out of date since the Light/War update. It is mentioned on many threads that when trying to breed an exclusive breedable dragon (such as Plankton, Poo, Great White, or Lava) the use of a legend dragon is highly recommended.
(I'm not one to say required, but I've yet to hear of anyone getting an exclusive after Light/War without a legend dragon).
So if you are looking for a Plankton dragon, my advice would be Legendary + Terra.
I usually recommend Terra, because it usually results in the lowest times for most dragons and you can get additional exclusive dragons since Terra is often a common element in exclusive dragons. (Sky, Angry, Lava, Poo, Great White, Diamond, Bat, Deep Forest, Plankton).
But if you aim is Plankton, Legendary + Sea is perfectly valid.
Yeah, Rawrshaq is correct. The easiest way to breed Plankton Dragon is by breeding a Lvl. 10 (or above) Sea Dragon and a Lvl. 10 (or above) Terra Dragon. The first result will be Mud Dragon and second will be Plankton Dragon. Try it. It worked for me :)
You know, whenever I start to get frustrated at not being able to get the dragon I want, I go and breed something else. Many times I've gotten the one I've been wanting by accident, trying to get something else. :)
DC is a game. It should be fun. Don't ever let yourselves get frustrated over a game, it's not worth it. After all, the journey isn't as much fun if you only focus on the destination. :)
Something else you could do, if DC starts to get the better of you -- log off, shut down, and go outside. lol