Re: Aquatic Plants Digest V2 #89

Greg Tong <gtong at sirius_com> write Wed, May 22:

>Subject: Green water fallacies?

>I've got another question for you all. Someone on the Goldfish List has
>stated firmly that green water is caused by incomplete biological
>filtration, that if our filters were working, there would never be green
>water. His reasoning is that green water algae can only live when there is
>ammonia around whereas "hairy algae" (his term not mine) can thrive on
>nitrates and phosphates. He claims this is why green water is *never* found
>in planted tanks.
>Neither his conclusion nor his assumptions along the way sound right to me.
>Advice? TIA.

Green water algae use nitrate very well.  I have seen this in algae
research literature, and I have also seen a quick greening response when I
have given a nitrogen-deficient tank with green water (well, yellow-green)
a small amount of nitrate.  In fact, formulas for nutrient solution mixes
for growing single celled algae always use nitrate.  I have had planted
tanks with green water, and I am sure that others have also.  The green
water algae are very strong competitors for nitrate,

Paul Krombholz                  Tougaloo College, Tougaloo, MS  39174
In hot, humid Mississippi where we havn't had any rain for four weeks.