I am getting ready to introduce CO2 into my heavily planted Fluval Edge, as soon as I can be sure my kh/gh is sufficient to keep things stable.
I have a ton of cherry shrimp, plus 8 juvenile neon tetras. I also have a lot of plants (java moss, java fern, cabomba, pearlweed, various anubias, rotala, subwassertang, amazon swords and micro chain sword, blyxa japonica, and some crypts).
My question concerns the risk of gassing my fish and shrimp. My understanding is that surface agitation oxygenates the water (as well as the plants during the day), but that CO2 will rise at night.
I can't add an airstone because the last time I ran one it caused splash that blew out my lighting system.
Is the CO2 generated from this system likely to overwhelm my fish and shrimp? If so, would putting less yeast and sugar in the canister decrease the CO2 output sufficiently?
This is the system I will be using: http://hagen.com/uk/aquatic/addinfo/co2system.html
For those who are not familiar with the Edge, it is a 6-gallon largely sealed aquarium, with a 5" x 7" or so open area for surface agitation and access, with a 20 gallon rated aquaclear power filter.
I have upgraded my lights with led bulbs and strips.
Thanks for any advice you can provide.