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Re: Strange water values, hypothesis

Re: white fuzz on CO2 airstone

Justin <justinf at zimmer_csufresno.edu> wrote:
> 
> I started a fermentation CO2 system on my new plant tank, and I=
>  noticed white fuzzy hair on the airstone.

IMHO (which differs from some) is that airstones are not a good idea
for CO2 injection. They are subject to plugging and with DIY this can
spell disaster. A simple method which works fine is to put the CO2
outlet tube into the uptake tube of a powerfilter or to connect it
to the aeration port of a powerhead. I use the powerhead method with
DIY CO2 and find it superior to other methods and just fine for
efficiency. It produces extremely fine bubbles. A clean airstone by
itself takes a fair bit of back pressure; this combined with the
18" of water pressure may cause CO2 leakage from any tiny leak.
Check it by blowing into the tubes. White fuzzy stuff is fungus I
think. Suggest removal and bleach or boil it.

Steve
> ------------------------------

Re: fish vs. plant discussion

Rich - Hextek at aol_com wrote:
> Sorry that fish are coming up when its supposed to be
> about plants, but they are an integrated part of the aquarium
> system.

Not at all Rich!! Yes it's about plants but also about the fish used
in plant tanks as well. Heck, sometimes we even talk about breeding
fishes (how great a plant tank is for it). Shaj, if you haven't 
already, how about posting the charter again?

Steve

> ------------------------------
> 
> From: Matt Rhoten <mrhoten at oz_net>
> Subject: Strange water values, hypothesis
> 
> tank parameters. 50G
> lighting is four normal-output 30W Triton fluorescent bulbs
> lit for approximately ten hours
> eleven Rasbora heteromorpha 1.5" and two
> three-spot or blue gouramis 3".
> 10-12 Hygrophila polysperma, and a few (possible) Egeria densa.
> 
> The normal water values are: temp 76-80F, pH 7.0-7.2 (LaMotte),
> carbonate hardness 1.7dKH (LaMotte), nitrite 0 (Tetra), nitrate 12ppm
> phosphate 0 (Tetra). I have had [some] green film algae.
> I do not inject CO2; I don't fertilize, no laterite.
> 
> Lately temperatures have been high, up to 84-85F.
> pH has risen to 7.6.
> Phosphate has risen to measurable levels (.1ppm). And, here's the
> weird part, nitrate has bottomed out at zero.
> 
> I am guessing that the plants are sucking the nitrogen
> out of the water faster than the fish are putting it in.

Close. What nitrates you had were used by the plants and cyanobacteria.
No new nitrates are being generated by the nitrogen bacteria cycle
because the plants will metabolize free ammonium quite rapidly.
Having low nitrates is not a problem; don't worry about that.

> They are also blocked on CO2 roughly as much as nitrogen,
> so are removing nearly all of it from the tank, which is causing the
> pH to remain high. I have no idea why the phosphate value is high.

Without artificial supplementation, CO2 will be in short supply.
Your plants are probably resorting to biogenic decalcification to
obtain CO2 from (calcium) carbonates. This will produce high pH and
if high lighting levels and low CO2 concentrations continue, result
in sky rocketing pH esp. for certain plants like valisneria which are
adapted for very hard water, low CO2. Phosphates are probably
accumulating from feeding the fish or from your water supply. Possibly
the latter since you change water regularly. I'd test your tap water
for phosphates and increase water change frequency to weekly or
twice a week until the phosphate concentration is lower.

> My plan of attack for the short term is to reduce the lighting for a
> while, aerate the water more (to get CO2 _into_ the water, of all
> things) and, God forbid, feed more heavily.

Reduce lighting period makes sense. Aerating the water won't increase
the CO2 concentration any; CO2 partial pressure in air is very low.
I'd suggest DIY yeast CO2 until you get the CO2 tank in place. Feed
more? NOT!

> For the long term, I plan to inject CO2

Good plan since you have moderately good lighting (sorry, MH spoils
a guy)

> add sodium bicarbonate to keep my carbonate hardness up and my pH
> stable

Some people suggest adding sodium bicarbonate to soft water for this
purpose. I'm not sure it's essential. Chemists, does this really buffer
the pH or just contribute to carbonate concentration?

> Does this sound reasonable? Or am I daft?

Reasonable, sure. I couldn't say about you being daft tho'; I hardly
know you! ;-) [joke de ba] The other thing I'd suggest in the short
term is turning those 10-12 H polys into 30 or 40 so that the whole
tank is fully planted. This will better utilize the available light
and nutrients and (hopefully) preempt an algae explosion. Longer term,
you would replace those Pollys with other, more interesting plants
to add visual variety and landscape your tank. Driftwood can look
really sharp (I've not done this). Stones and other objects in my
tanks tend to get covered with brush algae. I've used rocks for
landscaping to make terraces so the rocks aren't very removeable.
I think it's good to have two sets of rocks, some underneath for the
foundation wall and removeable slate ones to shade the others. The
slate rocks provide hiding places for the fish and prevent algae from
growing on the non-removeable rocks. Bleach on aquarium fixtures works
wonders for removing algae. Be sure to rinse well, use a chlorine
remover and let them dry thoroughly before putting back into the
aquarium to avoid getting chlorine in your tank.

Steve