What are the major expenses?

1
What are the major expenses?

• Tank and stand
• Light
• Substrate
• CO2
• Fertilizers

2
How to live on the cheap.

• Tanks and Stand -- buy used and pay no more than
  1-2 per gallon. Re-paint stand as needed. Hammer
  in a few boards to make it more sturdy/look
  better
• Lights -- use 48 electronic T8 fixtures that you
  can get at the hard ware store for 20

3
How to live on the cheap- substrate

• Substrate -- buy plain gravel or sand (also from
  hard ware store esp. if you can get the no-salt
  sand for icy roads)
• Supplement in moderation with things like
  peat/soil (1cup/ square foot) ironite (1
  T/square foot),
• I like to make clay balls with added nutrients
  and add them both before and after a tank is
  planted. I recently set up a tank with nothing
  but clay balls. And plain gravel

4
How to live on the cheap --CO2

• I have used yeast CO2 on tanks up to 180 gal.
  Also 75s, 65s etc.
• 2 gallons of yeast changed once every 3wks to
  month depending on the temperature works well. I
  dont rotate the bottles either.
• The key to long lasting cultures is allowing them
  to grow and be happy. Also a little basic
  knowledge of yeast growth helps.

5
Yeast Growth/metabolism

• Yeast can either produce energy by fermentation
  or oxidative phosphorylation (ox/phos)
• Yeast greatly prefer fermentation over ox/phos
  and will not start ox/phos until all the sugars
  are converted to ethanol.
• Ethanol is a good source of energy and in the
  presence of oxygen yeast use it up as well.
• Fermentation also produces 2 CO2 molecules per
  molecule of sugar-- as a by product. )

6
Why is just sugar and water not ideal?

• When you just add sugar and water to yeast, they
  are essentially starving to death.
• However the enzymes for converting sugar to
  ethanol are still in the cell and will work for a
  limited amount of time.
• Since the cells do not have what they need to
  make new enzymes as cells starve/run out of
  enzymes the culture produces less and less CO2.

7
Also, we add too much sugar.

• Ethanol and sugar are increasingly toxic to yeast
  at greater than 10 concentrations.
• Therefore 2cups (500ml) of sugar in 2L of water
  (25 sugar) is unhealthy for the yeast.
• It is also a waste of sugar because 10 sugar
  will yield roughly 10 Ethanol at which point the
  yeast stop growing anyway.
• Special strains of yeast, like champaine and wine
  yeast, have stronger cell walls that protect them
  from the Ethanol -- so they grow longer.

8
Happy yeast give you long, productive cultures.

• The solution is to give yeast less sugar and also
  supply them with the nutrients they need to grow.
  
• This will give you a long lived culture that
  produces a consistent amount of CO2, (they are
  not challenged by toxic conditions at the
  beginning and end)
• Also your yeast mass at the end will be alive and
  well and able to quickly start growing again when
  you add more sugar.

9
The Recipe!

• Improvise at will, but here is a good start
• Use 1 cup sugar per 2L H20 (tank water is great
  or dechlorinated tap -- chlorine, but not
  ammonia, kill yeast. ) (they like ammonia)
• Add 1-2 tsp of a protein drink mix
• (optional) Add 1 tsp of ammonium sulfate,
  otherwise use 1 T mollasses. (or both)
• 1 tsp baking soda is also nice to keep the pH
  from crashing (they like it gtpH3-4)
• Leave yeast from previous mix in the bottom.

10
Benefits/conclusons

• Growing yeast this way saves you time (less
  re-starting) and money on sugar and yeast.
• The only real extra cost is the protein mix, but
  you can use really old/cheap stuff.
• The key thing is that it has protein and
  vitamin/minerals, Anything that has yeast
  extract in it is perfect.
• (Even non-fat powdered milk will do the trick,
  but it will smell funny)