I have a Deltec PF601 (latest 5th generation) Calcium reactor and Avast Marine K2 Kalk stirrer. The Deltec is rated for 528 gallon tank and the Avast rated for 800 gallon tank/14 gallon per day of kalk. Asking $500 for the Deltec and $175 for the Avast plus shipping from 39301 area code. Thanks.