Battery Questions

[ccacher1]

I searched around on the forum and found many of the answers to my questions but still have a couple more about rigging up my fish finder and live well pump. I have a SLA 12v 9ah battery and am hoping to use just this battery to power both a Lowrance Elite-4x FF as well as a tsunami 500gph pump. The reason for me wanting to use one battery is because I have a smaller kayak and can't have the added weight if possible. The questions I have are...

1.) Is anyone else running a single battery this size or smaller for both?
2.) Can you just use an adjustable aerator head on the live well pump to decrease the water flow from a 12v battery or would I actually need to run a timer switch?
3.) If I do use a timer switch for the live well pump would this drastically increase my battery life?
4.) If a 12v 9ah battery simply isn't enough to run both for 6ish hours even with a timer switch, would a 12v 10ah battery be enough?

Thanks in advance for any tips/advice.