I have just done an overdose programme with Flourish excel (spot treating areas with the overdosage) and this is what I found -
it has lowered the pH of the water (not a bad thing as it was getting to 7.6-7.8ish, but I think the fluctuations caused flashing),
it dissolved almost all of my twisted val,
it turned my supposedly dwarf sagittaria into 20cm long leaves,
made my stargrass double in length over about a week and a half,
at the same time I stripped the piece of wood and scrubbed all visible algae and since then so far no more staghorn and beard algae.... I imagine it will slowly come back as I still have some direct sunlight on the tank,
and I must have killed some bacteria as the tank is just going through a mini cycle - not high numbers of anything but more than the next to zero levels they were at, should come right soon
....and finally I did upset the corydora. After a few days of overdosing mixed with normal dosing they were skulking around the bottom with clamped top fins. I did a couple of big water changes and they are happy again.
I will go find you the link that someone posted for me to read up on first before you do the overdosing thing.
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here you go - a thread within a thread within a thread
viewtopic.php?f=4&t=43475
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