"Dr_No" no wrote in message ...
So increased CO2 will reduce algae problems?


Plants need various nutrients in combination, different for each plant of
course. So if plants have lots of Nitrate, but no X, they will be limited by
the missing X. Since your plants aren't growing this leaves more Nitrates
(etc) for the Algae to grow. The old school of thought on this was to try
and limit the Phosphates to keep the Algae from growing. The new school says
give your plants everything they need to stay healthy and they will remove
the nutrients the Algae needs to thrive. This is why CO2 is recommended at
higher light levels, as it becomes the limiting nutrient.

Somewhat over simplified.


I will be running 2x125W Mercury Vapour Pendants so approx 2W/G
Tap water is fairly hard so I dont think pH will swing too much



"djay" wrote in message
news:usKwe.13239$Xr6.4673@trnddc07...

"Dr_No" no wrote in message ...
I'm in the process of setting up my 150 gal tank. Looks like my funds
wont stretch to a presurised CO2 setup so i am wondering if DIY soda
bottle/yeast CO2 systems can work with a tank this size?

I plan to use a powerhead into a gravel vac with bioballs/sponge to
disolve the CO2 so it should be pretty efficient at using what CO2 I
get.

How many 2l bottles would I need?

Thanks


I don't recommend DIY for this size tank. You WILL have algae problems
if you have 2W/G.

But if you DO decide to DIY then I recommend the 64 OZ plastic juice
bottles. Larger base and larger lid made it easy to fill with
ingredients and harder to tip over. You'd need about 3 or 4 of them to
get any decent CO2 production.

The problem with DIY is consistent production and with the peaks and
valleys in DIY your PH may (WILL) swing wildly.

HTH,

Djay