I use 3 1.5 leter coke bottles with another warming... that means that every time I use BBS its 36hours since I put the eggs into it.
In other words, say this morning I put eggs into bottle 1
tonight I put eggs into bottle 2
tomorrow morning I put eggs into bottle 3
tomorrow night I use bottle 1 and put eggs into bottle 4. After straining the BBS from bottle 1 I refill with sea water and allow the water to warm up. At the next feed, I put eggs into bottle 1 and use bottle 2... sounds complicated but its really easy.
If anyones interested, feel free to come around and have a look