In my opinion, that is not a solution...it is another problem. What you did was put a bandaid over the problem instead of fixing the underlying reason for BBA and string algae. BBA could have been eventually eliminated by the introduction of more co2, like you said that you already did. String algae occurs (if my memory is correct) in high ammonia situations with excessive nutrients. so doing a blackout for 3 days could have helped, along with changing yoru fert dosing schedule and adjusting y our co2 for a few days.Thank you all for your replies. I found a solutions. Siamese Algae Eaters. I picked up five this afternoon and placed in my 10 gal quarantee tank. I trimmed three stems just above new growth and put in the tank with the Siam...............
i highly doubt you have acquired crossecheilus siamensis. what you're looking for are chrossecheilus langei, if anything. search the site you'll see what i mean.
i agree, 5 is a bit much for that tank regardless of species.
if you got them at a lfs it's likely they were very hungry. maybe they were fed right, but it's doubtful until we know more about the store in general. that could be why they were so efficient at your cleanup. mine eat whatever they can get and graze in their spare time. however they don't eat primarily algae, they're more opportunists who are boisterous omnivores with a good appetite.
the excel spot treatment is to fill a syringe to the amount that you would dose your whole tank. turn off all of the filtration and water movement so that the water is very calm, you may have to wait a few minutes. then lightly inject the excel over the algae to be treated. you know that it worked the next day because it will have turned red usually.
as far as ammonia it may have been something as simple as pulling some plants out and disturbing the substrate. you may have kicked up a little ammonia that was a very quick spike and then dropped down to nothing very quickly, just enough to cause an algae outbreak.
bba can be caused by something stupid like fluctuation co2. doing your water change can be enough to throw your co2 for a loop. i like to do my water change an hour before my lights come on. thats when the co2 level in your tank would be the lowest. and as soon as i'm done with my water change i turn the co2 back on and everything goes back to the way its supposed to be for when the lights are on.