cyanobacteria solutions?

> I hate to pee on the parade, but IMO, the use of antibiotics in this 
> fashion is not the way to go.  You are getting more cyanobacteria than 
> you want because there is a problem with either the chemistry or the 
> biology of the system.  
> If I had to venture a guess, I'd say that your tank is probably short on 
> some microbes or very small arthropods that eat cyanobacteria.  Your tank 
> may have more phosphate than it needs.  Adding erythromycin doesn't take 
> care of either problem.  It will however eventually breed resistant 
> cyanobacteria and bacteria.
> Your analysis of the aftermath is essentially correct.  The cyanobacteria 
> died, their nutrients went into solution, where that bacame bacteria 
> food.  There was a bloom of bacteria, prehaps accompanied by a spike of 
> ammonia, which your plants probably helped with immensely.  Eventually 
> the system comes back under control.
> If anyone else tries this, you should watch the dissolved oxygen 
> concentration, especially at night.  Based on my experience with 
> antibiotic use in reef aquaria (where there is also a bacterial bloom) if 
> the bacterial bloom is sufficiently intense, you may lose some fish to 
> anoxia at night.  Theoretically, you could crash a tank this way, 
> although I doubt that will happen very often in practice.
> The cyanobacteria always comes back in reef systems if something is not 
> done to address the underlying problem.

I do not particularly feel that using the antibiotic in my tank is a good idea 
either, but I haven't come up with any sound advice on how to remedy the high 
phosphate or lack of microbe-eating bacteria situation.

I have a freshwater tank, well planted, and do bi-weekly H2O changes.  I've 
never seen the PH fluctuate (7.5), but over the past few months, the GH & KH 
have lowered.

Do you having any solutions to get rid of the cyanobacteria?  I've seen the 
phosphate filter pads but haven't tried them yet.  Are these effective?

Any comments would be appreciated!