Re: Aquatic Plants Digest V2 #85

>From: gtong at sirius_com (G.Tong)
>Subject: Re: Ammonium
>Help. Where does ammonium come from? I thought ammonia was what the fish
>secrete. If so, something must first turn ammonia into ammonium ... Where
>does that something come from? TIA.

Your pH.  Ammonia and ammonium are in equilibrium, the ratio determined by 
your pH.

>A related question: when one has a biofilter in a heavily planted tank,
>would the bacteria and the plants be in competition? If so, who gets what
>first? My guess is the filter gets the ammonia first because it's puming
>the water through while the plants stand around waiting. Thus, the plants
>are more likely to get only nitrates--which we now know they have a harder
>time making use of.

Wait a minute here!  Before the water get sucked up into the pump, wouldn't it
have to pass through the plants?  ;-)  I don't think you can reason it this 
way.  It's a continuous cycle, and I don't think all the ammonia/ammonium
gets converted to nitrate in one pass through the filter, nor is it all used
up by the plants on contact.

>From: mmclean at mindspring_com (Mark McLean)
>Subject: film on water surface
>Hi all,
>     I am new to planted tanks and am having a problem with my 125 gallon
>setup.  We are using vermiculite and soil under a gravel substrate.  The
>tank has been planted for two weeks now.  We are growing plants that do well
>in low light,  We have 160 watts on 11 hours a day.  Everything is growing
>fine but every day a slick clear film forms all over the surface of the
>tank.  The pH is 6.8 and the water is soft.  I have been skimming it off,
>but every day it returns.  Is this related to having plants ?  I have never
>had this problem in any other tank and at a loss as to what to do.  I would
>appreciate any help.  

Either creates turbulence on the surface with the water returned from your
filter or use a surface extractor attached to your cannister filter (if you
have one).

>From: duncand at sprynet_com
>Subject: DIY C02 recipie doesn't last
>I'm running one bottle on a 75g and one on a 50g. The recipie I got from a FAQ 
>file off of the AquaLink web site calls for 3 cups sugar and two tablespoons 
>yeast (roughly 1 packet) to the two litre bottle. The file states that this is 
>supposed to last about two weeks. I'm barely getting one week on mine.

That's way too much yeast, which uses up your sugar quickly.  I bet you got
a very strong output.  I use only 1 cup sugar and 1/2 teaspoon yeast in the
2 litter bottle.  Or 2 cups sugar and 1 teaspoon yeast.  Depends on how much
CO2 you want.  It usually last 2 to 3 weeks for me.  Reduce yeast if you
want it to last longer (with less flow of CO2).