"Graham Broadbridge" wrote in message . au...
" wrote in message
om...

If you raise the CO2 to 20-30ppm for the entire photoperoid and keep
it at that level consistently, BBA will stop growing. Try it. Then you
can see for yourself and stop going on a wild goose chase.

Okay Tom, I'm always open to an experiment :-)

My 55 gal is phosphate 0ppm , around 2ppm Nitrate (due to addition of KNO3
as required). CO2 is around 20ppm by calculation.

I still always get some beard algae growing somewhere or other.

I've just increased the kH to 10 dgh in order to obtain 30 ppm CO2.

I'll lete you know the results.

Regards
Graham.

Good idea but why not just add more CO2 and lower the pH, not add more
KH?
The pH is not going to change things by being another 0.2pH units
down.
Having to alter KH is a PITA if you don't have to.

It would not hurt to add some PO4 at that point also.
2ppm of NO3 is too low BTW and so is 0 ppm PO4.

You have co limtations occuring.
Your plants do not have enough C, N and P. Algae don't need much so
you can figure out who's going to dominate this situation quick.

Regards,
Tom Barr