Mine was likely the quickest meriting streak in an hour, although if we consider a 24 hour period (contemplating 24 UTC hours in a single day, but not trying out overlapping 24 hour periods on two consecutive days), we get (Top 20):
name user_from date nTx nMerits
qwk 24140 17/09/2018 423 602
DdmrDdmr 1582324 03/02/2019 254 257
qwk 24140 10/01/2019 91 155
dbshck 153634 15/12/2018 84 201
Halab 1053119 24/12/2018 82 84
LoyceV 459836 05/01/2019 82 107
qwk 24140 11/03/2018 81 107
Dabs 54791 25/01/2018 81 123
dbshck 153634 18/01/2019 71 293
qwk 24140 22/03/2018 66 71
teramit 158960 23/06/2018 65 175
lcharles123 171309 10/02/2018 64 75
suchmoon 234771 04/03/2019 64 375
qwk 24140 21/11/2018 63 69
dbshck 153634 17/09/2018 62 135
qwk 24140 14/06/2018 61 93
klarki 407174 31/05/2018 59 74
DannyHamilton 60820 20/02/2018 59 61
qwk 24140 27/07/2018 55 87
qwk 24140 24/10/2018 54 72
To be fair, @qwk takes the lead in a 24 hour period.
If we look at it from who merited most people in a single second, @LoyceV ruled until @Theymos came along and sent 15 negative TXs from the forum account.
name user_from date nTx nMerits
(Bitcointalk Forum) 0 2019-02-05 22:07:10.000 15 -102
LoyceV 459836 2019-01-05 10:25:35.000 4 6
LoyceV 459836 2018-10-13 08:18:22.000 4 4
LoyceV 459836 2018-11-17 11:38:43.000 4 4
LoyceV 459836 2018-10-15 20:24:28.000 3 3
LoyceV 459836 2019-01-05 10:25:32.000 3 3
LoyceV 459836 2018-10-15 20:11:19.000 3 3
LoyceV 459836 2019-01-08 18:09:10.000 3 3
LoyceV 459836 2018-09-15 14:59:35.000 3 3
LoyceV 459836 2018-09-10 08:15:05.000 3 3
LoyceV 459836 2018-10-10 12:04:18.000 3 3
LoyceV 459836 2018-09-15 14:59:31.000 3 3
LoyceV 459836 2018-11-01 12:14:50.000 3 3
LoyceV 459836 2018-09-15 14:59:32.000 3 3
LoyceV 459836 2019-01-07 13:07:54.000 3 6
LoyceV 459836 2018-09-20 18:08:42.000 3 3
LoyceV 459836 2019-01-05 10:25:34.000 3 5
LoyceV 459836 2019-01-05 10:25:37.000 3 3
LoyceV 459836 2018-10-15 20:11:20.000 3 3
LoyceV 459836 2018-10-15 20:26:32.000 3 3
On the receivers side of the TX weve got (Top 20):
name user_to date nTx nMerits
theymos 35 25/01/2018 205 756
explorder 1108331 25/01/2018 101 227
theymos 35 01/04/2018 72 170
Lutpin 520313 25/01/2018 67 312
theymos 35 24/01/2018 54 198
theymos 35 17/09/2018 49 110
theymos 35 26/01/2018 49 248
BOMG 1033117 31/01/2018 33 131
Vod 30747 25/01/2018 33 66
numanoid 333524 25/01/2018 29 55
EFS 140584 25/01/2018 28 94
TMAN 98986 26/01/2018 27 146
exus 231031 25/01/2018 26 59
theymos 35 27/12/2018 26 42
satoshi 3 25/01/2018 26 226
TMAN 98986 27/01/2018 25 59
theymos 35 09/01/2019 25 76
kaar 1439008 26/01/2018 25 60
Mitchell 113670 25/01/2018 24 54
mstfprcn 915311 25/01/2018 24 102
@Theymos rules the list, having received 205 TXs in a single UTC day.