new starter is weird
I started a pineapple juice based starter 6 days ago, and it was nice and bubbly and active on day 4. Then I started feeding it twice a day 1:5:5 with whole wheat flour. That's when things went weird. It does doubles and domes nicely after 7-8 hours, and stays domed and continues to go past doubling after another hour or hour and a half. It has some nice bubbles going on inside, below the top, but the top itself is only mildly bubbly. And it doesn't smell all that convincing. Just not fresh and sharp. Not foul, just not overly yeasty and not the way some other starters have smelled before (like Hefeweizen, mmmm). What the heck is going on? Does it need more time? Should I feed it more? Less? I keep it at 75 degrees: too warm/cool at this stage?
Every starter is a unique culture, and will look, act, taste and smell different from any other. However, there may be a small chance that you are feeding more often than necessary. If a good, strong yeasty smell is what you're going for, try one of two things. Feed at a lower ratio of food to culture, or feed less often. If you can observe your starter throughout the day, the best way is to let it get as high as it can, not just double. When it reaches the point that it isn't going any higher, it needs to be fed. However, even that is a range of time, and can be manipulated according to how you want your starter to behave. I feed mine at the beginning of the peak rise. If you want it to get more of that aroma, you can wait until it is just beginning to fall, then feed it. The time in between that beginning point when it has just reached its peak, and the end point when the peak is regressing, can be a few hours, and anywhere along the way, it can be fed.
As for the ambient temperature, I don't think 75F is a problem. Most starters can live in a freezer, although they will become dormant, and can survive to just a little over 100F ambient temp. The temperature you keep it at will affect how active it is, which affects how much it needs to be fed. You can manipulate both feeding ratio and ambient temperature to get your starter to react within a specific amount of time. For instance, in my 68 degree house, I feed my starter at a ratio of 1:2:2 of starter:flour:water to get it to just peak in 12 hours. During the summer months, I've fed as much as 1:8:8 to my starter in a 12 hour period, and it was past its peak and hungry by the end of that 12 hours.
I just read your post again and noticed that you are feeding your starter whole wheat flour. That will affect both how active your starter is and how sour your bread will be. You can probably just lower your feeding ratio to 1:4:4 and check it at the 12 hour mark, to see how it has grown. It should do well. Another thing is, unless you really want your starter to be whole wheat, or you want a sour bread, you could change to unbleached all purpose or bread flour and feed it even less. That will save you money in two ways: the amount of flour you use, and the price of the flour you use. The whole wheat flour is great for starting your culture, but isn't necessary for maintenance feeding.