So, I store most of my eol bulbs in a freezer. All but two of them were dead ones, 1 was a Generic f4t5/d from late 90's then second one was a modern Eiko f4t5/d. The Eiko f4t5/d was pink at first but is now at its standard color after a month in the freezer, my generic bulb seems to have gone super mercury starved or dead. When I put it next to plasma ball it glows very dim pink but it may be the light from the plasma coming through it. Could the cold temps have depleted the emmisive coating or done something to the mercury?

At low temperatures the mercury comdenses (and diffuses into the metal parts), so the lamp then becomes mercury starved until the mercury gets released by the heat once turned back on. But the release uses to take some time, easily quite a few hours of operation, before it starts operating normally.

Why do you need to store them in the freezer? There's no point!

At low temperatures the mercury comdenses (and diffuses into the metal parts), so the lamp then becomes mercury starved until the mercury gets released by the heat once turned back on. But the release uses to take some time, easily quite a few hours of operation, before it starts operating normally.

How about the filaments and the emmisive coating on them?

@RCM442 It uses less space and there's a chance the eol ones may go mercury starved.

Simply keeping them in the freezer is not going to make them go mercury starved. (and will deff not burn out the filaments.)
It will make them *look* mercury starved when first started...until they warm up.

I've gotten one pink through freezer treatment, it lasted like a few weeks till it burned out. While time was a blur when it went mercury starved I remember putting it in the freezer, within 30 minutes I took it out and it was pink.

It get temporarily starved as the mercury condenses, but once it warms up for some time, it releases the mercury back. So this has nothing to do with the mercury starvation failure at all.
What I don't know is, whether the lack of mercury (before it get released back) may cause the remaining gas to erode the emission coating a bit faster. But if it does o, I would expect this to be very marginal.

And generally for any failure, temperature cycling stresses are one of the prime accelerator for any damage or excessive material wear (material fatigue, cracks propagation,...). So storing them in freezer makes the temperature difference the lamps have to go through way greater than normal operation (about double temperature differences for the glass,...).

So storing the lamps at somewhat cold place, yes. What matters more is the temperature being stable. But what is bad for storage is the humidity. Storage place has to be dry, to prevent metal corrosion. And mainly there should not be any conditions for condensation. And causing humidity condensation is the one thing messing around with frozen objects causes pretty readily.

So no, intentionally storing the lamps in a freezer is not any good idea. Moreover when that freezer could be used for something more useful (like storing food) or does not have to consume the electricity when it is not needed for long time.

You're saying the picture has nothing to do with actual mercury starvation?

How much thermal stress would actually caused issues like that because usually from room temp. to freezer wouldn't do much but from hot operating temp. then into a freezer could cause issues I guess though wouldn't it be more contamination not mercury starvation?

If the bulb remain sealed, there is no reason for any contamination. Assume tha lamp was properly cleand inside during manufacture.
What does contaminate the gas fill is if it gets overheated. The thing is, practically all solids absorb some gasses. But when you heat them up, those gasses get released. Normally the bulbs are heat treated to some extend during evacuation step, so all the gasses that may have become relesed during operation later on, get released during that dvacuation step and get pumped out. But when, after the lamp is sealed, you heat up some part beyond what was this treatment (above the designed operating temperatures), some more gas that was still trapped there may get released and then poison the lamp fill.
But cooling it down can not release anything. It may only absorb some of the fill (e.g. the mercury) and that then becomes missing (lamp runs starved) until it gets released again once it warms up back to normal again (it recovers). The "mercury starvation fault" means a permanent, non recoverable loss of mercury, e.g. when the mercury chemically reacts with some components or contaminations. Again this is more likely happen by overheating the lamp (heat accelerates reactions), or it is just part of the normal lamp wear.

Normal ambient temperatures are about 25degC, normal operating temperatures of many tubes are around 40degC, so that means one power cycle means warming it by 15degC up and then cooling it 25degC down after power down. Now if you store the lamp just at the fridge temperature (not freezer), lets say at 5degC, the temperature difference becomes 30degC, so already practically double. When the freezer is at -15..-20degC, the total difference between running 40degC and the freezer -15..-20degC becomes 55..60degC, nearly quadruple from the normal indoor temperature difference. So all the stresses caused by difference in thermal expansion among materials that have to meet (e.g. tye wire seals, cap attachements,...) become 4x larger in cycle stressing. That is nothing small for a material fatigue development (crack propagation,...).
Yes, hotter running modern lamps the ratio is smaller, but still it is rather large.
So what you do get more likely, is various fatigue cracking and seal failures.

Nice explanation, sadly the bulb that I thought was super mercury starved it dead. I've tried it on a lot of ballasts but nothing happens.