After battling BBA and BGA at various times, with varied successs, I decided to do a 3 day blackout. This is the 125 gallon that I had asked various questions about before. This is one of the threads describing my situation.

Why is BBA growing on my diffuser?

I wrapped the sides of the tank (except the back) in Glad garbage bags. The back has a vinyl blue background already, so I didn't touch that. For the top, I just throw a large heavy blanket on. I turned off all the lights and the CO2 and left for a 3 day weekend.

When I got back and slowly peeled back the coverings, the fish all went nuts of course. Plants were all ok. A little bit of BGA (the main reason for the blackout) was all gone. However, it didn't look like much, if any, of the BBA had died. Is that normal? Will they die over the next while? I've got my CO2 cranked back up now, with the normal lighting schedule of 8 hours.

I am concerned that I didn't do the blackout long enough. Oh yeah, one thing I omitted. I did a large (50%) water change immediately before and after the blackout, along with a gravel vac.

BBA is not affected by a BO, BGA is and that's what a Blackout is for really, not BBA.

Too address your tank's issues.
Add nutrients
Add more CO2
Add more surface moevement if it's low.

You can add about 50% Excel to 50% water and spray on thr infested leaves, wood etc. That will kill it.

Do a 50% water changes 2-3x a week till the BBA doies and turns white.
You can be less aggressive but you need to focus on the plant growth.

That's what keeps it from starting up in the first place, all algae are a sign some plant requirements are not being met.

Regards,
Tom Barr

Ah...thanks Tom. I was mistakenly thinking that all algae would be affected.

I've been spot treating with Excel full strength (about 15 mL at a time). I guess it's time to get serious. I'll up the water changes (I am currently doing 50% twice a week - I'll go to 3 times a week. Guess I'll have to go to EI type dosing then, since the fish won't be able to keep up. I had been only adding Epsom salts, K2SO4 and trace twice a week.

I'll turn up the CO2 a bit more, although the drop checker is showing I have good levels. Water movement is pretty good, as I have an FX5 and an Eheim 2028 in there, so I don't think I can improve it any and have my fish not be stressed.

Try this for BBA:

Take 1/3 pure Excel and 2/3 water, add to a spray bottle.
Add 50mls of Excel and 100mls of a water and spray as much as you can evenly on infested areas till gone.

Do a 70% water change or more, enough so that the fish are not flopping.
Spray affected area

Refill tank quickly thereafter.

That + water changes, trimming, add 5-6 baby SAE's.
Consider CO2 mist. Also, add less light intensity(this is good for most species fo algae issues).

I think you'll find a lot more success with using all of these methods together.
This is about as aggressive as you can go.
Which is a wise idea to beat any type of algae back asap.

Use "many little hammers" to beat the infestation back and restabilize the tank system.

Regards,
Tom Barr

Thanks Tom. I'll try the Excel/water spray idea.

I have already incorporated many of your ideas from previous threads.

1) I am misting CO2 from two diffusers. One on each side of the tank. That's working well.
2) I added 6 SAE's. Only 2 survived the original onslaught of the now 10 inch Chocolate Cichlids. They are now healthy and fat on algae and leftover foods. I guess I might have to get a couple more. There are also 2 bristlenose plecos and 1 giant Gibbiceps pleco, plus 4 corys in the tank, but of course they only do cleanup and remove green algae, not BBA.
3) This is a low light tank already. 144 watts (60W T8/84W t5) on the 125 gallons. Full 144 watts on for 8 hours and 60 watts on for 1 hour before and 1 hour after.

I'll go the aggressive route and try all your suggestions together (3x 50% water change, the Excel spray, reducing photo period a bit more).