If you're nesting loops then for each $idomain_host you're running through the whole $domain_purchased array (or vice versa). This doesn't sound like what you want. It sounds like you want
domain_host, domain_purchased,
domain_host, domain_purchased,
...
Etc.
So...
reset($domain_purchased)
foreach($domain_host as $idomainhost)
{
list($k,$v) = each($domain_purchased);
...Do stuff with $k, $v and $idomainhost...
}
Is this what you're after?