You are not supposed to be able to keep both of them healthy unless your group is really big. Just make one starve and keep fed up gamabunta.

If you are able to register for gnw means you have 12 active people and with 12 active people is relatively easy to gather 3200 chakra per week to keep it fed up (the other 300 comes from group summoning attempts).

But if your mates prefer to not claim the daily activity packs because they level freeze, if your mates prefer to not care about trading and prefer to avoid rolling the max number of rolls per day in the group wheel because they use coins only in inner gates then is not oasis fault.

That said I think too that gamabunta summon capture should grant a lot more chakra per run (so would make sense to select it instead of snake... ) and that is very unrealistic to have a group big enough to be able to keep both of them full fed up (for both you need around 25-30 really active people that do not level freeze, something possible only on new servers, newly merged serves or thanks to the help of legions of alts).

My group is level 12. I get 6 packs per day from daily activity + an average of 4 more from the group wheel out of the 13 tries (usually two of the rolls are the packs, sometimes is 1, sometimes 2, sometimes 3). Out of 10 average packs i get in average 1 full set per day + 1 additional full set every two days thanks to trading with group mates. In 14 days are 21 sets. 525 group chakra. 525*12 = 6300. Considering the chakra we gain from group summon capture the chakra needed is 6400 in two weeks. Yes, theoretically is 100 chakra short, but, i did not take in account the other 35 chakras that stockpile in that time and that i am not able to trade. If all of the 12 sell them are 35*12*2 = 840 additional chakra. So, an active group of 12 people is perfectly able to keep 1 summon fully fed up. The problem is in keeping two.

So, if you are not able to keep it fed up is because or your group mates do not trade or because they do not fully spin the group wheel every day if really they are not level freezing or simply because your group is too low level to have enough spins per day (but since your snake is level 95 this is not the case).

If you have to choose one summon to keep fed up chooae gamabunta. Gives more additional stats to your groupmates than snake and owns way higher stats than snake (a starving gamabunta at 40% easy kills one snake at 100% on par level)