Do These Work Well?

[Discuslove]

Saw these on ebay for cheap and i was wondering if anyone has used them and if they are any good?
 
http/www.ebay.com.au/itm/Root-Tab-Capsules-Aquarium-Plant-Fertilizer-Capsule-60pc-120pc-/121141871317?pt=LH_DefaultDomain_0&var&hash=item1c349e42d5&_uhb=1
 
same thing??
http/www.ebay.com.au/itm/Root-Tab-Capsules-Aquarium-Plant-Fertilizer-100pc-Sz00-/111143897568?pt=LH_DefaultDomain_0&hash=item19e0b149e0&_uhb=1

 

[phishyphil]

Root Tabs are really usefull in the planted aquarium and last anywhere from 1-6 months depending on the tablets and plants growing from them.
 
Root tabs are really neccessary for heavy root feeders such as swords and certain crypts. 
 
Swords will develop nicely with root tabs, and crypts will grow rapidly in my experience, developing roots up to a foot long in my case at times, however I do run ferts, High light and pressurised co2.
 
Root tabs are great, but not used the brand you have chosen to look at, but look at the more reputable brands and compare their make up, they should be similar so no reason why they shouldn't work!