Well I have a purge of 2, maybe I should try it with 1 then? 
"analytics_storage_type": "redis",
"analytics_storage_config": {
"type": "redis",
"host": "redis",
"port": 6379,
"hosts": null,
"username": "",
"password": "xxxx",
"database": 0,
"optimisation_max_idle": 100,
"optimisation_max_active": 0,
"enable_cluster": false
},
"purge_delay": 2,
"pumps": {
"mongo": {
"name": "mongo",
"meta": {
"collection_name": "tyk_analytics",
"mongo_url": "mongodb://mongo:27017/tyk_analytics"
}
},
"elasticsearch": {
"name": "elasticsearch",
"meta": {
"index_name": "tyk_analytics",
"elasticsearch_url": "liwnd070.my-tts.net:9200",
"enable_sniffing": "false",
"document_type": "tyk_analytics"
}
}
},
"uptime_pump_config": {
"collection_name": "tyk_uptime_analytics",
"mongo_url": "mongodb://mongo:27017/tyk_analytics"
},
"dont_purge_uptime_data": false