Fade LEDs on and off when the power is switched on and off
I'm still a complete novice when it comes to electronics so I was wondering if anyone here would be able to help.
I'm rigging up some LED lighting for my aquarium which is set to switch on and off with timers on the mains supply to the house. The timers switch on/off the power transformers which supply the LED lights. I would love to find a way so that when the power comes on the lights fade on and when it goes out they fade out, would be nice if it was a long fade too, maybe 15-30 minutes, ideally 30 mins to an hour.
I am guessing there would have to be some pretty big capacitors involved to that would fill up, increasing the brightness as they goe, when the power comes on and slowly discharge as the power switches off.
Another thing to note is that I am using 2 different LED systems.
The blue LEDs are using standard LEDs that are sold in blocks (3 LEDs per block, I'm using 3 blocks, so 9 LEDs total) and are designed to run on 12v. I am currently running them on 6v as they are pretty bright, but if the circuity could have them fade over an hour I would like to put them up to the full 12v.
The white LEDs are 4 of 3w luexon star type LEDs that are running in serial. The system goes mains > 12v transformer > 3w LED Driver > LEDs. Here is a link to the driver I'm using
I assume that the fade device would have to go between the driver and the LEDs?
Thanks for any help you can give me.