Ok here's the deal

I have 50mbit internet and have wpa security

However the nintendo ds wifi doesn't support wpa, but only WEP

The problem I have is that WEP doesn't support 50mbit and will cap my internet at like 20mbit, which is pointless

Removing the security isn't an option

Can someone with knowledge of the subject help me out? Like is there a WEP style security that supports 300mbps.

get a better router or something

i'd say just go out and get a nintendo wi-fi usb adapter

You could always connect 2 wireless routers to your modem, one cheap one to use for ur DS and one for other faster use.

Or get your hands on a nintendo wifi usb adapter as mentioned (eventho i think they dont get made anymore).

there sold on some websites still ;p