VHO flicker

[Delphinus]

Oh wait, I just realized something. Monday I had forgotten to turn my fan back on after I had been playing around with things, so things got rather heated in there that day (luckily the tank temp never exceeded 30C). But the hood was probably pretty hot, and maybe that explains the blackening and demise of the old VHO tubes.

But it doesn't explain the flicker on the new tubes. So, still need some suggestions on how to improve things there.

I've never used VHO actinics before. Do they need a burn-in period maybe? They're URI tubes, I thought those were the best to get.

BTW, it's just a standard tar ballast, I wish I could have an Icecap, maybe one day.