[Hallyx]

And whenever doing a 40-50% water change, on any size aquarium, it is always safer to remove the fish.

Understanding that I highly value your opinion in these matters, respectfully, may I ask why?

 

[Hallyx]

In a small 'aquarium' (bowl really) you have no choice since it's impossible to maintain a cycle and you are forced to do 100% changes.

I'm sorry, I don't understand this. I'm not trying to "maintain" a cycle in my smaller tanks; I'd rather do frequent water changes.

Why should a keeper scour everything every week as you have described? Nobody is that compulsive, are they?

 

[Hallyx]

Sorry, Geomancer, I read the scour part in from other posts describing 100% changes.

I'm constrained by space to runnung 2.5g tanks ("bowls," if you will); my split 5g is inconveniently large. That's the one I could cycle, but filter noise and fear of (frequent) power outages keep me at my every-third-day water-change schedule. I never see NH3 over .25ppm and my NO2 and NO3 are, of course zero.

I totally agree with not stressing the fish with routine removal from their tanks. Even though mine are apparently tolerate it well, I'm sure they don't like it much. I siphon and vacuum alll changes, so I don't have the cord bundling, dumping in sink, redecorating hassles.

I'm working up the courage (and finances) to build a 2.5g NPT. If that works, I'll do my 5g.