why use an external service?
some pseudo code:
numberofrounds=100
numberofwalletsperround=100
maxtimeperround=60
for (i=1;i<=numberofrounds;i++)
(
for (j=1;j<=numberofwalletsperround;j++)
(
array(i,j)=rpc.getnewaddress
)
)
for (i=1;i<=numberofrounds;i++)
(
for (j=1;j<=numberofwalletsperround/2;j++)
(
amountosend=rpc.getbalance(*,10)/(numberofwalletsperround-2*(j-1));
rand=random(max=amountosend/(numberofwalletsperround-2*(j-1)+1))
rpc.sendmany array(i,(j*2)-1) amounttosend-rand array(i,j*2) amounttosend+rand
wait(random(max=maxtimeperround/(numberofwalletsperround/2)))
)
)
while(rpc.getbalance(*,10)!=rpc.getbalance(*,0))
(
wait(10)
)
)
fee= 0.005*numberofrounds*numberofwalletsperround/2