New flourescent bulbs have a hard time starting

[Beff]

I have a saltwater fish only tank that has two 36" single bulb fixtures that use 25W T8 aquarium bulbs.

I decided to replace the old bulbs as they were many years old and showed signs of blackening on the ends.

I purchased two Zoo Med T8 aquarium bulbs with the same kelvin rating as the old bulbs (10,000K). However, both bulbs flicker for several minutes before fully turning on. The old bulbs (which still worked) never had this issue. Also, all the previous bulbs never had this issue.

The new bulbs were shipped to me. Although the box showed some signs of shipping abuse, the bulbs and manufacture's packaging appeared OK.

The fixtures are 27 years old and have no starter. They were bought at a local electrical lighting supply store.

What is likely causing the new bulbs to have a hard time starting up? Again, the old bulbs worked fine...that is, no flickering or starting issues.

Any thoughts are appreciated.

-Jeff

 

[Vinny Kreyling]

The only other thing is the ballast.
Sounds like shop fixtures & it may be cheaper to buy new ones. Check prices.

 

[Beff]

Update

Update

Here's an update just to close the loop...

After struggling a couple of times to ignite over the course of 2 days, the bulbs are working fine now. They ignite immediately without flickering. It's almost as if the new bulbs had to break-in.

I searched the internet have have never found any discussion about florescent bulbs needing to "break-in". But it's the only explanation I can offer.

cheers, Jeff