I use OpenDNS.com free personal account to block by category at a childrens home and school. It will support what you are trying to do. You can also block specific domain names and whitelist sites that may be blocked by category. Since I also have dynamic IP, I also use dns-0-matic. The router tells dns-o-matic when the ip address changes and sends the updated ip to opendns. There are youtube videos on how to set up dns-o-matic on asus router available. I can send you screen shots if you get stuck. This video covers the steps involved:Help, Anyone got any good advice on blocking Snapchat, instagram etc.
many thanks in advance
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