Hello again,
from what you've described, I'd say you have the pesky pouch snails. I read through the posts and when I made mine above forgot that you had indeed mentioned that you are cycling.
Now, you can use Potassium Permanganagte if you want to, but it will be back to square one with the cycling. Weigh 9 ish days lost cycling against instant snail AND their eggs death.
If you do not want to do that then try Flubenol 15. Get it from here:
http
/www.flubenol.co.uk/
4 grams of the stuff is enough and will cost you £4.75 incl p&p. when you get it, divide it into 4 equal parts and store each amount separately in little bags. Take the first amount and mix it up in a mug of water and then pour straight into your tank. Do this weekly for 4 weeks AFTER your usual weekly water change.
I am currently doing this now and the snails have all but disappered - I am experimenting with using Flubenol 15 as a TOTAL and SAFE solution to ridding tanks of snails as it is beneficial to the fish and fillter bacteria, does not effect the plants in any way and appears to be OK when used with inverts and crusts (i.e. crabs, shrimp etc).
Note that Flubenol 15 is not sold as a snail killer - it is for killing parasite worms. A side effect of its use however is that it kills snails.
For the record I made a thead that tells you how to sanitize plants BEFORE you put them into a tank:
http
/www.fishforums.net/index.php?showtopic=167686
(I wish I knew this information before I put plants stright into my tank and got infested with what seems to be the same damn snails you've ended up with! I have easily picked out at least 300 to 400 of the damn things over the last 4-5 months).
GL
Andy