Questions about 8 day old wild yeast starter

I'm new to wild yeast starter and I so appreciate the information I've found on this site.  I have a few questions and I'm sure people have posted these before but I'm not finding right now.

Eight days ago I started a rye/pineapple juice starter and it worked beautifully thanks to recipe here.  Day before yesterday I tried to increase volume and activity has really slowed down although still getting bubbles, just not as active and no hooch to pour off like on days 5 and 6.  I believe I increased too much and too soon.

Today I poured off all but 1/2 C. and separated these in two containers (1/4 C. starter each).  To one I fed 1/4 C. flour (with 2 T. being rye) and 1/4 C. water + 1/4 t. ACV. 

To the other starter, I added 2 T. rye and 2 T. pineapple juice.  10 hours later they both have some bubbles but nothing dramatic.

What do you suggest I feed with (rye, all-purpose, water or pineapple juice?) and how often ? to build up the volume and strength?  I'd like to have a good 2 cups starter so I can use 1 to 1 1/2 C. in recipe, then have enough to feed and build back up.

Thanks!  Mrs. Chiu