green spot algae

tacks

Junior Poster
Jan 12, 2006
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:) I have made a mistake with my kh. I have added a lot of bica. thinking I had to raise my kh. By the time I figured out my error my kh was off the wall. Iam now getting it down too 10 or 179 ppm. The amont of co2 has not been good for the fish but I have an air stone. My ph goes between 6.50 - 6.92 Since I have added all this co2 I have noticed more spot algae which I hate. I have been using ro water for water changes to bring my kh down. any suggestionsfor the increase of spot algae? I do add tmg and nitrates are at 25 but I do keep my phosphates a little low. thanks Ed
 

Tom Barr

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Jan 23, 2005
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Re: green spot algae

The two main variables for GSA: low CO2 and low PO4.

So you need to add PO4, like to 2-3ppm and make sure you have good stable CO2 ppm levels.

KH should not effect anything here. Co2 stablility definitely will.
Blend tap with the RO to get about a KH of 2-3 or so, if you want a higher KH etc, that's okay too.

Regards,
Tom Barr
 

VaughnH

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Jan 24, 2005
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Re: green spot algae

You might want to consider adding Ca and Mg too, since you are diluting GH as well as KH when you add RO water. Don't drive the GH too low.
 

tacks

Junior Poster
Jan 12, 2006
9
0
1
Re: green spot algae

:) thank you that is a very good point. I have never really checked GH and this would be a good time to start. I have my KH at 9 andI am happy with that as is gives me a good co2 reading Thanks Ed