Don't know what power your other bulb is, but the link you posted for the 24" version is only 17W. Assuming the other bulb is the same, that's a total of 34W over what area/volume? What size is your tank?
For arguments sake, lets say 24"x18"x24" (guess from a pic you put on about the trickle filter), that's 45 US gallons. The rule of thumb for anything other than LEDs is 4W/Gallon for low light corals, and 10W/Gallon for high light requirement corals. That's assuming it's not a deep tank.
You have 34W/45Gallons = 0.75W/Gallon
You need to upgrade to T5s as a minimum, and need to fit in 180W minimum, ideally 450W. Better would be to go with LEDs, as they work out way cheaper over time.