Algae production, CO2 consumption, O2 release

[cnmcalpi]

Assuming Algae production is photosynthetic and releases O2 while consuming tank CO2.

Answer this,

I have seen where people have suggested using a lid to slow evaporation on an ATS. If a tight fitting lid is used in an acrylic enclosure, is that not going to supersaturate the air around the alga in o2? Does it even matter since the nutrient sink in this case is the water and not the surrounding air?

Also,

Is the consumption of CO2 at the prescribed rates of algae production outlined in building guidelines enough to raise average ph measurements?

[SantaMonica]

Welcome,

The vapor partial pressure of water is much greater than CO2 or O2. Thus, a seal will allow internal humidity to reach 100%, thereby slowing further evaporation.

However the seal will not hardly increase internal CO2 or O2 vapor partial pressure at all, and thus they will not be slowed down.

[cnmcalpi]

So the closed enclosure is not going to affect respiration of the algae? The algae will only respire within the water its fed? Both consuming CO2 and releasing O2? I assume this is the case, just brainstorming here.

[kerry]

I thought I had better growth when I blew a fan into my water fall scrubber area. I didnt do any real test to confirm but after I took the fan off it seemed to have less growth.

[SantaMonica]

If the question is supersaturation, then no it will not. If the question is will it slow growth, no it will not.

Algal metabolites go to the water, then to the air, so the thinner the water is, the better it transfers. This is the reason for bubbles; when a bubble touches the algae, the water layer is so thin it's almost gone, and metabolites flow freely from the algae to the water to the air.

Yes, a scrubber can usually increase pH. by 0.1 or 0.2