"flupke" wrote in message
...
Hi,

i have a question regarding fertilizing plants and CO2.

I found an article on making your own mixture of K2SO4, KNO3, MgSO4
and trace elements to fertilize plants.
(http://www.cam.org/~tomlins/algae.html)
Now, if you use tap water, it will already contain most of the above so if
you
add such a mix, wouldn't that bring to many nutrients into the water?
Or are potassium and magnesium pretty rare in tap water?

Also, if you start using this DIY fertilizer, are there testkits to
measure
those elements or do you just go by trial and error?

The reason i want to try this is that i'm having a slight increase in
algae
growth
(hair algae). I use a liquid fertilizer but i don't think it's adding to
much elements
that are also usefull for algae (sera florena). But on the other hand, i'm
not sure
it contains potassium which seems like a must have for aquarium plants and
to
fight algae.

On CO2: my CO2 levels are way to low (+-1.2 ppm, PH 8, KH 5)
so i'm also going to build a DIY CO2 system. It seems easy enough.
Anyway, if you buy one of these systems, what would be the initial cost
and how much do pay to keep it going?

Regards,
Benedict



dosing ferts is dependent on a number of things, probably most importantly
is how much light are you using. If you have a low light tank, low light
plants then CO2 is not going to help much and fets, whether dry dosed or
PMDD stuff will increase your algae as the plants don't grown fast enough to
use it up. If you have high light, fast growing plants then the increased
need for CO2 and fertilizers. A DIY CO2 system costs next to nothing
depending on what you use. It can be a couple of 2 liter bottles, some
airline tubing , yeast, sugar and a bit of baking soda. I still use DIY on a
33g tank but changed to a compressed system for my 77g.

Rick