| | Re: glutaraldehyde instead of excel
First, the calculations are correct. Metricide 28 is 2.5% glutaraldehyde and adding 200 ml of water to 300 ml of Metricide 28 will give you a 1.5% (Excel strength) solution.
In my experience GSA is not effected by Glutaraldehyde, adjusting my phosphate dosage seems to be showing some progress with that.
BBA is tough stuff! Typically I dose the Seachem recommended 'Initial dose' at water changes and 2X the recommended 'Daily dose'. If there is a heavy outbreak on plants I remove any leaves that are heavily affected. Any hardscapes, heaters, etc I remove from the 'scape and treat with 50/50 bleach/H2O and then scrub with a brush and use a very heavy treatment of Seachem Prime to nuetralize the bleach. For stubborn patches in the tank I turn of all filtration so the water becomes still and then "spot treat" the heavy areas 'painting' them with 1.5% glut and an oral dosing syringe. I am careful when 'spot treating' not to exceed the recommended ml dosage per gallon.
After the BBA dies then my SAE move in and eat the dead 'tufts' leaving me BBA free!