| The information provided at that website is rather too general for my liking. However, since this technology is getting rate as safe for human habitation, it is very likely fine for your use. I note that some venting is suggested for homes with very "tight" construction. I suspect your filter house is not as air tight as the latest energy-efficient home designs. There is probably some leakage around the door and window (assuming you have one?). If you were really careful to build it "tight", then you may need to crack the window a hair to allow some outside air seepage. Since no problems to date, I'd not worry too much. But, I think you are right to stay alert to any change in koi behavior.
About 7 years ago my wife & daughter painted a bedroom at the opposite end of the house from where I keep aquaria. It was a latex paint with very little odor. It was a warm season and the air conditioning was on. Within 24 hours every guppy in the aquaria was dead. All other fish seemed O.K. Fumes from the paint were the suspected culprit, although it could hardly be smelled at that end of the house. No air pumps are used on any of the aquaria. Aeration is accomplished through water movement and wet/dry trickle filters maximizing exposure to the atmosphere. So, I learned the hard way. |