WARNING a double dose of Excel may kill more than your algae

[Merrilyn]

Although it's been common practice to add a double dose of Seachem Flourish Excel to kill off Black Beard Algae, it may kill more than you bargained for.

Read this thread :-

http://www.discusforums.com/forum/viewtopic.php?t=16924

A double dose resulted in the tragic death of a beautiful breeding pair.

[prenzi]

Hi all,

well, to add to the downsides of the Seachem Excel Flourish I'd like to mention that we recently had a huge outbreak of blue-green algae in our tank which was about to smother all our plants. This happened within 3-4 days. While temp, pH, all salts, trace elements, CO2 etc were perfectly OK, within range and unchanged compared to before we had been using the Excel stuff at the manufacturer's recommended dose for a while, then I got lazy and a bit slack on the water changes, and suddenly we had it.

Ceasing to use Excel, doing a few big water changes and fertilising for a few weeks with nitrate only solved the problem pretty quickly; what I suspect is happending is that the glutardialdehyde is broken down / metabolised into "whatever", accumulates in the tank and provides excellent growing conditions for BGA.

Did anyone else ever experience this ?

Cheers, Florian

[ILLUSN]

most likely the bga was caused by a drop in redox caused by a the change to your water change routien.

BGA wont survive with a high redox, thats why H2O2 works so well on it.