[Amps] Storage of 813 bases amplifier

[JEREMY ENGBROCK]

I have a home brew amp that uses 2 813 tubes in parallel in a grounded grid circuit.  Do to my recent move to a condo I have to store the amp for a few years. What if anything can I do to keep the tubes in good condition. When I built the amp I had 12 813's but 8 of them were gassy or had other issues. So now I have the set in the amp and a spare set. I am storing the amp inside a climate controlled closet. Will it help to run the heaters on the tubes for say 24 hours every 6 mo or so? What else do you recommend if anything? 

73,  Jeremy N0NZG