Using Excel to Kill Algae | SFPT008

Art PennomHelp with Algae, Podcast, Pro TipsLeave a Comment

blue green algae cyanobacteria

Using Seachem’s Excel to kill algae is effective

Excel to kill algaeExcel contains glutaraldehyde. According to our friend Wiki:

Glutaraldehyde is an organic compound with the formula CH2(CH2CHO)2. A pungent colorless oily liquid, glutaraldehyde is used to sterilise medical and dental equipment. It is also used for industrial water treatment and as a preservative.

It is what causes Excel to kill algae as both a spot treatment or tank wide treatment. However, use with care as shrimp and sensitive fauna/flora may have an adverse reaction.

How to use Excel to kill algae

First and foremost, please make sure everything else is in order. Things such as water change, proper fertilizer, CO2, lighting, temperature and clean filter. Without curing the cause of the algae in the first place, killing it will only be a temporary thing. No one wants that.

My preferred method of using Excel to kill algae is to spot treat. Take a plastic syringe or pipette and put it right up to the algae. Hit it and wait for two days.

The algae should turn white and die. If it doesn’t, hit it again with, perhaps, a little bit more. Keep doing this for a couple of more times. If it doesn’t die, then it’s resistant and this technique won’t work.

You can also try a full tank dosage if you have a lot of algae. I would make sure that the tank inhabitants are not sensitive and definitely don’t try this if you have shrimp. Start with a regular dose, then the next day go up to 2 times then wait two days. If the algae has not turned white and begun to die, hit it again with 3 times the dose.

I’ve used the above method successfully many times over the years. I wish you good luck and please let me know what your experience is in the comments.

Here is a link that you may find useful:

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