Algae and Algae competition

> From: "T. Misiak" <misiak at fsu_fsufay.edu>
> Date: Wed, 20 Sep 1995 17:28:25 -0400 (EDT)
> Subject: algae bloom


> 	I have recently purchased some new plant fertilizers 
(Kent) whi
> contain a lot more iron than the Tetra FloraPride I was using.  
> overdosed the fertilizer and with the lights on for more than th
> have been on.... I have green water and my angelfish don't look 
> and aren't eating well.  


> What's the best way
> to get rid of this problem?  I stopped fertilizing, reduced ligh
> 8, and have been doing 10% water changes daily.  The water is st
> and one of the angles hasn't eaten since this started (6 days no
> other one eats but not as well as it once did. 

No matter what the substance, overdosing with _any_ chemical calls 
for _large_ water changes to reduce the concentration quickly.  
Iron and many other trace elements are very toxic at high levels. 
One of the most common forms of accidental poisoning in small 
children is from getting into Mom's iron supplement.

Do several 50% water changes (daily) to get the levels down.  Then 
be Very_ careful when you re-introduce.  Anyone using trace 
elements should have an iron test kit to make sure levels don't 
get too high.  When using a new trace element supplement, it is 
usually wise to start with 1/2 the recommended dose and work up, 
to prevent this sort of problem.


Subject: Plants competing with algae

Stephen Pushak wrote:

> This would imply that a brand new tank with new gravel should
> have fewer algae problems than an existing fish tank which
> has introduced plants and increased lighting. The difference
> would be the initial concentrations of nutrients. I have a
> feeling that many experienced plant people prefer to start
> with fish first rather than from clean? (contrary to this)

Not this experienced plant person!  I have a feeling this is a 
hold-over from the days before balanced trace element supplements 
and good lighting.  Without bright lighting, a little bit elevated 
nutrient level is not a big problem.  There is nothing to feed 
plants in the sterile environment of a newly set up gravel based 
tank without aquarist intervention, so it made sense to wait until 
the fish had fertilized the substrate.  This method, of course, is 
still a valid approach as long as optimum growth and wide species 
diversity is not a top priority.
> I don't think 
> dense planting or anything except algae consumers is going to
> eliminate algae that is already present. You have to remove it.
> You cannot starve algae to death.

I don't totally agree with this one.  I'm not sure "starving it to 
death" is the right term, but in my experience, many algae species 
have very specific needs, and if these are not met, they quickly
perish.  I have put badly algae infested plants from the wild into 
a tank to have it disappear in no time.  I have also seen cases of 
algae infestations disappear quite rapidly in tanks where the 
owner got high nitrate/phosphate levels under control.  OTOH, 
those algae that have the same basic needs as desired plant 
species can be trickier to control!

Karen Randall
Aquatic Gardeners Assoc.
Boston, MA