Question 1

What causes this product to kill algae, and does it kill anything else (like beneficial bacteria)?

Accepted Answer

I bought the Seachem Flourish Excel because it seems to be the best solution to a Black Beard Algae problem I'm having, and after studying what it does, and how it does it, I too was worried about the Beneficial Bacteria in my 2 large canister filters.Couldn't find a direct answer to that question, so I sent an e-mail directly to Seachem Laboratories. Here is my question to them and their reply......
Message: I have a 72 gal heavily planted community tank and am having an outbreak of Black Beard Algae. I purchased your product as it seems the best solution to the problem, but I need a question answered before I can use your product. I now understand how your product works, but will this product also kill off the Beneficial Bacteria inside the Seachem Matrix Bio-Media of my 2 large canister filters?! Crashing the cycle in my tank is not an option. Is this product (Flourish Excel) safe to use for the bacteria that maintains the nitrogen cycle of my tank, or will it kill the bacteria in my filter media along with the Black Beard Algae and crash the nitrogen cycle of my tank? Need a straight answer, please, Thank You
Seachem Support 10304 (Seachem Laboratories)
Sep 23, 2022, 16:31 ADT
Hi there, thanks for reaching out! 
 No, Excel will not affect your biological filtration if dosed appropriately. 
 Hope this helps! 
Seachem Support 10304
Needless to say, I am very relieved, and pleased. Now I can start the process of getting rid of that Black Beard Algae and not worry about crashing my nitrogen cycle. 2 Thumbs Up to Seachem Laboratories!

Question 2

are they copper free?

Accepted Answer

No. They contain 0.001% copper. Though people have used them in shrimp tanks without a problem, others have had shrimp die, particularly if the tablet got stirred up from the substrate (rescaping, fish burrowing, etc). If there's a chance of your substrate being disturbed, I'd recommend going with API Root Tabs instead, as they do not contain copper.

Question 3

How I use this for my tank 20 gallons

Accepted Answer

Per the instructions:
"On initial use or after a major (> 40%) water change, use 1 capful (5 mL) for every 40 L (10 US gallons). Thereafter use 1 capful for every 200 L (50 US gallons) daily or every other day. For smaller dosing please note that each cap thread is approximately 1 mL."
1 cap = 5ml
1 cap for every 50 gallon equates to 1 ml for every 10 gallons or 2 ml for 20 gallons.

Question 4

Is the product compatible with freshwater invertebrates, like amano shrimp?

Accepted Answer

I use this product on a regular basis and I have snails and shrimp in my tank.  No problems.

ASIN	B001NTE30A
Brand Name	Seachem
Customer Reviews	4.7 4.7 out of 5 stars (3,420)
Global Trade Identification Number	00000116050708
Item Form	Granules
Item Weight	0.01 Ounces
Liquid Volume	10 Gallons
Manufacturer	Seachem Laboratories, Inc.
Manufacturer Part Number	075434
Model Number	18799
UPC	000116050708 781163380566

Seachem Flourish Tabs 40 Count by Seachem

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