I have 5 serpae tetra 's and 5 high fin black skirt tetra's. I have two 14" petco bubble bars. I have the four port petco air pump running two out puts into one for one side and the same for the other. With each bar with there own line. The PETCO brand pump I got it because it has a control on it to turn it up and down. I have been waiting to see if one of the bars will fill in the whole length and it hasn't yet even took a toothbrush as advised from a PETCO employe. So if it doesn't fill in all the way going to take it back and get another one. And as far as the bubble's or the pump being loud its not to bad really. And if it then I just turn down the pressure on the pump. And as far as making the water dirtier haven't really noticed. I'm running a fluval 306.
I have the two Petco bubble bars too -- I believe they're two 18" though; can't recall. At any rate, they almost fill the back of my 60 gallon, which is around 48" long. To be honest, I have gone through many brands of these so-called bubble wands and stones, and I have had the most success with the Petco bars. No kidding. They haven't crapped out on me yet. You mentioned you have a Petco brand air pump too -- I actually had a Top Fin brand pump at one point (Petsmart's house brand), their top of the line one, but man was that thing NOISY and it didn't put out much power. I switched to a Rena Air 400, which is seriously the best pump commercially available in my experience, and supplement it with a Tetra Whisper 60, which isn't that great, but together, they individually feed the two bubble bars. The Rena is clearly the more powerful and superior product, as the bar fed by the Tetra doesn't spit out bubbles from all its pores while the one fed by the Rena comes out full force, like powerful, rocketing bubble curtains.
It seems, though, with all the aeration in my tank from these two bars (not covered by the gravel substrate), it has lead to more calcium and lime deposits on the edges of the back of the tank and on the filter plastics -- plus, it seems to make the water look a bit "club soda" like, what with all the bubbles popping and fizzing everywhere. Interesting that you can't seem to tell if the bubbles are affecting your water's clarity.
As a side note, your fish must be really small -- I don't see them anywhere in the photo!