The former Brentford and Shrewsbury striker had been on loan from Hayes and Yeading for the previous three months starting eight games and making a further seven sub appearances, scoring twice.
The 26 year old will remain at Edgar Street until the end of the season.
Later Elder commented about the deal:
Gota say a HUGE thank u to everyone sendin me tweets of praise an goodluck from all ova the country. Feelin very blessed rite now #bigsmiles
Apologies to the Hereford fans bt looks like u'll hav to put up wit me for a lil while longer.