Angels at surface and Fertilizers

Subject: Re: Angels at surface

> Bob -- It sounds to me as if the angels aren't getting enough ox
> started up my new 75-gallon the first of the year I was using on
> canister filter with the output near the bottom of the tank. Tho
> would be fine during the daytime when the lights were on and the
> producing oxygen, in the morning, when the lights had been out a
> had been using oxygen all night, the fish were at the top of  th
> finally added an air pump with airstone and haven't had any prob
> The disadvantage, though, is that the surface agitation from the
> takes some of the CO2 out of the water, which means plant growth
> as vigorous.

Why don't you put your air pump on a timer set to run opposite 
your lighting?  Then you can run it only at night, when your fish 
need it.


 Subject: Fertilizers

Dorothy Brandon wrote:
<snip good run down of tank parameters>

> Rationale for using Florapride (FP) in this tank: I started addi
> several months ago because the stem plants always showed signs o
> deficiencies and slowed growth if the water wasn't changed weekl
> contains mainly K and Fe, both of which I need in excess of that
> my water and Flourish. Other macro nutrients are plentiful (C, H
> S) as well as the micros Mg and Ca. FP is convenient and not all
> expensive. I have access to the chemicals, so I might make my ow
> Concerning transitory Fe levels: I raise the Fe level to ~.25ppm
> it decreases to between .1 and .2 in a week, then to about .05 a
> two weeks, so my measurements indicate iron is utilized or oxidi
> The K deficiency: Because iron levels are high enough with the a
> FP, I recently started adding small quantities of my own K2SO4 s
> apparent change in algae.  If I can get organized enough, I woul
> add measured, increasing amounts of K2SO4 on a regular basis whi
> monitoring P, N, and plant/algae growth. I just started monitori
> levels, so I  don't have a baseline yet.
> Assumptions: 
> With only small amounts of peat and laterite, these plants are o
> most of their nutrients throught the water column or water circu
> through the gravel plus any mulm settling into the gravel. This 
> the K additions easier to evaluate.  
> I share the frustration of not having a K test kit. Knowing appr
> concentrations and the rate of uptake would be beneficial with m
> am hoping that N and P will gradually be reduced, at which time 
> able to formulate a K/Fe additive that will replace the FP, redu
> merely to the time it takes to make it and the energy to fuel my
> carry it home. Come to think of it, Tetra might be cheaper 8-).

With a KH of 10 and a pH of 7.8, you only have about 4.7 mg/l CO2 
in the tank.  I suspect that your plants are CO2 limited more than 
anything else.  Why not see if you could drop the pH to about 7.4 
by adding another yeast reactor or two?  This would give you a CO2 
level of about 11.8.  I think you'd see a great improvement in 
your plant growth, and probably see those nitrate and phosphate 
levels start to drop off.


Karen Randall
Aquatic Gardeners Assoc.
Boston, MA