Kummer confluent hypergeometric function `Hypergeometric1F1` has many zeros. Using your definitions:

 Plot[eq[1, 1, λ], {λ, 0, 1310}, PlotRange -> {-.25, .15}, Filling -> 0]

![enter image description here][1]

You see that the 1st four roots are less than 200, give it a list of initial values in that range - large enough to get all the roots:

 Union@Round[ED[1, 1, Range[1, 200, 5]], 10.^(-6)]
> {13.0143, 47.552, 101.833, 175.854}

Some of the roots will be the same maybe with a small difference in the very last digit. This is why you need `Union` and `Round`.


 [1]: https://i.sstatic.net/qNoc8.png
 [2]: http://dlmf.nist.gov/13.9