Re-brew tastes more 'thin' than original...?

[Slounsberry]

Hi all, started all-grain brewing about a year ago and the first beer I made that I was really happy with was a SMASH Czech Pils (no discernible off-flavors, to my palate at least, and my father-in-law who gave me the recipe idea from his home brewing days liked it too, success!) Got around to brewing another batch of it last month with a few minor tweaks, and the beer tastes kind of thin or watered down. Hoping more experienced brewers than I can help identify what might be the cause!

(For both of these I do about 3.5 gallon brew sizes)

Brew #1:
~ 50% distilled water/50% tap from Charlotte, NC
6lb German Pils malt
0.75oz Saaz @ First Wort
0.75oz Saaz @ 20 min
0.5oz Saaz @ flameout (literally right when I shut the burner off)
WLP800
----
Target OG: 1.041 Actual OG: 1.038
Target FG: 1.010 Actual FG: 1.006
Bottled with carb tabs

Brew #2: (the thin one)
~50% distilled water/50% tap from Greenville, SC
6lb German Pils
0.75oz Saaz @ 60 min
0.5oz Saaz @ 20 min
0.75oz Saaz @ whirlpool 15min @~125F
Wyeast 2007 (WLP800 not available at new HBS, I think I read this is the same strain?)
----
Target OG: 1.041 Actual 1.038
Target FG: 1.008 Actual 1.006
Bottled with Corn Sugar

Now that I write these things out side to side I'm going to need to go back and poke around in Beersmith to see why I changed the hops the way I did. I know I was trying to get more hop aroma, hence the larger amount and more specific steep temp, but I don't know why I would have changed the bittering and flavor amounts and addition time for the bittering... Could that have an effect on 'thin' taste?
Finally, I mention that I was in different cities for these because I'm curious if water could have an effect. Kind of hoping not since I don't want to dive into water chemistry just yet, but throwing it out there anyways! (FWIW, my second brew in the new city is just about carbed up and the one I tasted the other day didn't seem thin. But it's also a different style, Festbier, so I have no idea how water chemistry would affect the different styles.) I have access to the water profile for the new city if anyone wants to know anything there, but don't think I have it for Charlotte.

Thanks in advance for any pointers you can provide!

 

[Biscuits]

I wonder if it is the corn sugar at bottling. I know when I bottled and I used corn sugar, it always gave me an off flavor that I couldn't place but could be perceived as "thin".

 

[flars]

Did you treat the tap water with Campden. The two cities may have different levels of chlorine or chloramine. The mineral content of the brewing water will result in different tastes. Was the mash pH and sparge water pH the same?

 

[Pappers_]

Very difficult to diagnose like this. First, 'thin' and 'watered down' aren't flavors, they aren't something you taste. You might mean that the second beer has a lighter mouthfeel than the first? If that's it, it could be the difference in the yeasts, it could also be related to the mash temperature. In terms of 'watered down', you might mean that it is lacking in some flavors that were in the first beer, less malty or less bitter. If you can identify what is lacking, then you can fix it.

We've all brewed beers that weren't as good as a previous version we had brewed - don't get discouraged!

 

[Slounsberry]

Did you treat the tap water with Campden. The two cities may have different levels of chlorine or chloramine. The mineral content of the brewing water will result in different tastes. Was the mash pH and sparge water pH the same?

Didn't do anything to the water aside from cut tap water ~1/2 with distilled. Just got a pH meter a few days ago so I've never done any messing with pH either. What effect would chlorine/chloramine differences have? I know mineral content can change taste, etc. but since I don't know the differences between the cities I guess I was just wondering if it would be possible to say with some confidence that it was the water, or possibly something else.

Very difficult to diagnose like this. First, 'thin' and 'watered down' aren't flavors, they aren't something you taste. You might mean that the second beer has a lighter mouthfeel than the first? If that's it, it could be the difference in the yeasts, it could also be related to the mash temperature. In terms of 'watered down', you might mean that it is lacking in some flavors that were in the first beer, less malty or less bitter. If you can identify what is lacking, then you can fix it.

We've all brewed beers that weren't as good as a previous version we had brewed - don't get discouraged!

Fair enough, I suppose those two words aren't technically flavors/tastes, but whatever the right term might be that's how I would describe it and how my wife described it too. She wouldn't know any of the more technical terms so I figured if we both had the same perception that might mean something.

I suppose if I had to pick perhaps it's lacking in body and/or maltiness. I hit 150+/-1 for both mashes, and the FG and OG are the same between the two so I was thinking it wouldn't be body related, but perhaps there's more to that than just the basics that I understand? You mention the yeast. I checked again and it looks like I was wrong, the Yeast 2007 I used is the Budweiser strain (lolwaterybeer), not the Czech strain I meant to get (2001 apparently). So outside of gravities being the same (which I think means they attenuate the same(?)) perhaps the WPL800 one gave me more maltiness than the Yeast 2007.

I've been trying to avoid getting into water chemistry since that just seems like another complication, but I have access to the profile in my new city so I suppose it wouldn't hurt to start considering that, too. Especially as I try to re-brew and improve on recipes.