Post erythromycin cloudiness

Hi everybody,

I wish to report the following:-

Noticed the presence of the distinguishedly-smelling cyanoalgae/bacteria in
my 100g tank. Threw in 2 tablets of 250mg erythromycin which solubilized
within minutes. Water remained very clear.

3 days later, cyanoalgae began to fall apart. 1 week later, the tank is
entirely free of the thing! Water remained clear.

On the 14th day, noticed water turning slightly cloudy which continued to
get worst. This lasted for 6 days, after which the clarity began to improve.

No water change was performed during the entire period. 

Erythromycin, being an antibiotic, must have affected the biological
filter. The effect peaked roughly from the 14th day. It took about 6 days
for the biological population to recover enough to carry on its job of
water polishing and filtration.

Since only 500mg of erythromycin were used (unlike earlier suggested dosage
in the mails)in the 100g tank, it can be seen that its effect on the
cyanoalgae was astonishing. Hence to avoid further detrimental effect on
the b/filter, use only the minimal. I will try out only 250mg should there
be a future outbreak of the cyano stuff again.

APD members are welcome to comment.