Bought a 2nd hand Aquaclear HOB

[Rickus]

Im not sure if this is the 50 or 70.

what media do i use inside of it and in what order do i refill or pack the media.

Thanks, if someone can please help.

[Singularity]

you can use basically anything you want...
i would put a sponge at the bottom, then some bio media ie ceramic rings or some small bio balls and lastly some purigen, but thats just me.

[Verndog]

I normally chuck what it comes with and replace with biobeads. Works for me.

[azurekoi]

I used to just keep the sponge and chuck the carbon and zeolite bag... Sintered glass rings did the rest... In breeding tanks I used to hang one of those guppy tanks below the waterfall return and fill it with filter floss... massively increased the bio area plus added bonus of the clearest water I ever saw....