How Many Bubbles?

[Samuel G. Kramer]

Two weeks into my first fish tank and things are going pretty well.
16 of 17 fish alive (one of four Neon Tetras was swimming vertical on
the third day and has disappeared, probably dead inside an ornament).
Water tests come out good, and I just exchanged 10% of the water for
the first time without any problems.

I just installed a 23" bubble wand at the back of the tank, just above
the gravel, and hooked it up to a Tetra air pump desiged to handles up
to 40 gallons (which is VERY quiet; I have to touch it to see if it's
running). My question: How many bubbles should I produce in my 29
gallon tank? I can make three or four columns on the low side, or
make a wall of bubbles on the high side (which is a little noisy).

The bubbles are fairly uniform in size, that's not my question. My
question is how many bubble should I make for the fish to get the
benefit of aeriation. I would like to use as few as necessary to keep
the noise down.


Sam

[Billy]

"Samuel G. Kramer" > wrote in message
...
> The bubbles are fairly uniform in size, that's not my question. My
> question is how many bubble should I make for the fish to get the
> benefit of aeriation. I would like to use as few as necessary to
> keep
> the noise down.
>


IMO, bubbles don't do a very good job of aeration. The important
thing that must happen for good gas exchange is the surface of the
water must be broken, either by a powerhead aimed at the surface, or
a filter output splashing a bit as it enters the tank.
What type of filter are you running on this tank? What were the
actual results of the water tests? I'm a bit concerned that you
waited 2 weeks to do your first water change.

billy

[NetMax]

"Samuel G. Kramer" > wrote in message
...
> Two weeks into my first fish tank and things are going pretty well.
> 16 of 17 fish alive (one of four Neon Tetras was swimming vertical on
> the third day and has disappeared, probably dead inside an ornament).
> Water tests come out good, and I just exchanged 10% of the water for
> the first time without any problems.

Sixteen fish in a new tank may give you an ammonia and nitrite spike
(cycling the tank), which will need to be monitored and addressed. Be
prepared to do a lot of water changes until the cycling is complete, or
pursue other cross-seeding methods to add bacteria (used filter media,
bio-spira starter culture etc). http://faq.thekrib.com/begin-cycling.html

> I just installed a 23" bubble wand at the back of the tank, just above
> the gravel, and hooked it up to a Tetra air pump desiged to handles up
> to 40 gallons (which is VERY quiet; I have to touch it to see if it's
> running). My question: How many bubbles should I produce in my 29
> gallon tank? I can make three or four columns on the low side, or
> make a wall of bubbles on the high side (which is a little noisy).

If the tank has sufficient water turbulence from the filters, then the
*required* number of bubbles is zero. Many (most) people operate their
tanks with no air bubblers. Any bubbles you want to add is your
preference. They will slightly increase the O2 levels in the tank :o)
they add some noise :o( and increase turbulence :o| (which can be good or
bad, depending on the set-up, type of fish etc).

> The bubbles are fairly uniform in size, that's not my question. My
> question is how many bubble should I make for the fish to get the
> benefit of aeriation. I would like to use as few as necessary to keep
> the noise down.

Depends on what characteristic you define as a benefit. If it's the
extra O2, then it would be very effective at a low setting, as it's the
surface area of the bubbles x contact time in the water. Many very small
bubbles drifting upwards slowly will re-oxygenate the water better than
fewer larger bubbles racing to the top.

hth
--
www.NetMax.tk

> Sam
>

[Alpha]

Exactly 100 ;) Sorry could not resist.

[Logic316]

Samuel G. Kramer wrote:
>I would like to use as few as necessary to keep
> the noise down.

Hi Sam.
If you want to be precise, you'll need to use the scientific method.
Otherwise, with all the different factors involved (number/type/size of
tank inhabitants, water temperature, ammonia and other dissolved
chemicals, etc) I think even the most experienced aquarist would really
only be guessing. Set the aeration to a comfortable noise level, then
buy yourself an oxygen test kit (available at most fish stores) and
monitor the o2 level for the next few weeks (taking samples every few
days). Ideally, you want to tune the aeration level to get the highest
o2 concentration with the least amount of noise and power consumption.
Keep in mind that warm water holds less oxygen than cold water, so be
sure to test the water in your aquarium when it's at it's warmest
extreme. Also, high levels of ammonia reduce the amount of dissolved o2,
and although one should monitor and keep ammonia levels down in the
first place, a little extra aeration provides some insurance in case it
spikes up. And as NetMax mentioned, lots of tiny bubbles produce better
aeration than a few big bubbles and with less noise as well - airstones
are great for that, but I think you may find according to your tests
that you don't even need one.

- Logic316


"Thieves respect property. They merely wish the property to become their
property that they may more perfectly respect it."
-- G.K. Chesterton

[Dick]

On Sun, 31 Jul 2005 09:21:48 -0400, Samuel G. Kramer
> wrote:

>Two weeks into my first fish tank and things are going pretty well.
>16 of 17 fish alive (one of four Neon Tetras was swimming vertical on
>the third day and has disappeared, probably dead inside an ornament).
>Water tests come out good, and I just exchanged 10% of the water for
>the first time without any problems.
>
>I just installed a 23" bubble wand at the back of the tank, just above
>the gravel, and hooked it up to a Tetra air pump desiged to handles up
>to 40 gallons (which is VERY quiet; I have to touch it to see if it's
>running). My question: How many bubbles should I produce in my 29
>gallon tank? I can make three or four columns on the low side, or
>make a wall of bubbles on the high side (which is a little noisy).
>
>The bubbles are fairly uniform in size, that's not my question. My
>question is how many bubble should I make for the fish to get the
>benefit of aeriation. I would like to use as few as necessary to keep
>the noise down.
>
>
>Sam

Just for comparison Sam, over a month ago I removed all bubblers from
my 5 tanks. The 75 and the 29 gallon have a heavy fish population.
This started as an experiment to see how long these tanks would go
without electricity/air bubbles during a power outage. The first few
hours I watched closely for fish moving to the top and sucking air. I
went to be, but checked first thing the next morning. No sign of low
oxygen. As I considered the significance, I realized the mineral
deposits on the tank would be reduced as it was clear it was the
popping bubbles that were spreading the mist above the top, even to
the top of the light hood. I long knew I was getting a green mold
from the bubbles. Finally, not all 5 air pumps were of equal noise
output, no air, no noise. I won't mention use of electricity, but say
10 watts over 24 hours every day of the year must add to the electric
bill.

I have often argued for bubblers in the past, but I have changed my
opinion. I do like the wall of bubbles to look at, I do believe the
arietation helps keep temperature more consistent around the tank and
keeps solids suspended getting more into the filters, but cutting out
the green mold and eliminating the mineral deposits won out.

dick