Java Heap Space error sending emails

Hello

I am a new user in the forum and to pentaho generally and need a little help.

I have a pentaho job that gets a list of emails from a database table and then sends an email to each of those addresses (about 250 of them). I get a java heap space error. I increased the Java memory by changing spoon.sh to 1024. This improved things a bit in that the process nearly made it to the end rather than falling over half was through.

My steps are
Attachment 15860

1. transformation to get email addresses & links
this uses a table input step to get the data and copy rows to result set to pass back out to the parent job
Attachment 15861

2. Job to send emails
This job executes for each row from the result set which are put into parameters and has an email step to email the email address links in the parameters.
Attachment 15862

Any help would be appreciated, even if just an explanation as to why I get the memory error. The only thing I can think to do is to split the whole process into 2.

Thanks

Sarah