Ricky...please clarify...

Did you really mean that in four years you have not removed any of the finished worm compost? If so, that is likely your biggest problem.

No I haven't I was told that I didn't have to.

How big is that bin?

Ricky,

According to the book "Worms Eat my Garbage" you needed to harvest the bin every three to four months--depending on the size of the bin.

If you don't harvest, the bin eventually becomes more and more toxic to the worms. They grow smaller and smaller and reproduce less and less until you have zero worms.

I suggest you harvest the bin immediately.

How big is that bin? Is it an indoor or outdoor bin? What else can you tell us that will help us help you?

You might not need to harvest the whole bin every few months but harvesting the castings out of say half the bin every six months (alternate halves) would probably benefit your worms.

We have a 2' by 4' outdoor bin (warm climate) and we use a screen layer to make harvesting finished castings easier. We started by filling the bin half way with moist shredded cardboard and let the worms live in that and fed in that and added bedding to that for the first 6 months. Then we put a layer of window screen over the whole lot and added more moist bedding and food on top of the screen for several more months. As the worms moved up we started checking under the screen to see how "finished" the bottom layer of the bin seemed. Finally we could lift the screen out of the way and scoop out the castings from the bottom (still needed to sift through it for worms and cocoons.) Then dump the content of the screen in the bottom of the bin, lay the screen back on top add more bedding on top of screen and start the cycle over again.

As to how fast worms will grow and reproduce. The numbers given are usually for absolute best conditions possible. So, the type of worms you have will and the climate or conditions where your worm bin is will affect how fast the worms actually reproduce.

I've been told that a treat of an occasional sprinkling of corn meal can really get your worms in the mood but then again, perhaps they actually want the sexy music and mood lighting.

One thing I have never done is take the compost the worms have made out and start again with new Coir etc, does this have any bearing on what's happening? I want to try and use these for fishing eventually but I need enough to keep going, I haven't used any yet.

Ricky...Re harvesting your bin. This is also from Worms Eat My Garbage, by Mary Appelhof:

"Your particular goals...will help decide....That is, to harvest extra worms for fishing, you will have to change the bedding more frequently. Plan on doing this every two to three months, and figure that it is a high-maintenance system."

Hope this helps. :)

EGADS ricky! Four years!!
The place I bought my latest batch of worms from suggested that to harvest in a hurry, or almost hurry, you might want to put a big slice of watermelon, or some melon, face down at the top of the bin, right on the dirt. Put a cover on top, if you don't have one already. A day or so later many worms will have climbed up onto and into the slice.

Now put this worm ridden slice of watermelon onto another bin, or holding bin you have prepared. Then go through the now almost empty-of-worms-bin, with latex gloves on, and remove any other worms you can find. Put them in the holding bin too. I am not sure, but I think your holding bin will just need 'browns.'

If you don't have a garden, find someone who does to give all that rich worm casting dirt to. (I'll take it!! But something tells me you are no where near brooklyn ny, right? 'Wormery' sounds..very unbrooklynish)
Then get the old bin ready to be the new bin, with coir, newspaper, food scraps and after a few days put the worms back into it.

I haven't done this with my indoor worm bin yet, as it is new. But I have done something like this with my outdoor bins several times. That's why I have two, I move worms from one to the other.
How does this sound to those more experienced with indoor bins?