Question Summary:
Is it allowed to make wudhu with tea?

Question Detail:

Is the wudhu valid that has been made with tea (without milk and sugar). Just plain water, that has been mixed with tea.

Answer :

In the Name of Allah, the Most Gracious, the Most Merciful.
As-salāmu ‘alaykum wa-rahmatullāhi wa-barakātuh.
In principle, if a solid item is placed in water and it does not change the saylan (flow) and riqqat (thinness) of water, it will be permissible to perform wudhu with that water regardless of the colour or taste changing.   
Since tea leaves are a solid, it will be permissible to perform wudhu (with tea which has no milk and sugar in it) regardless of the colour and taste changing  as long as the riqqat (thinness) and saylan (flow) of the water has not changed. 
 
And Allah Ta’āla Knows Best
Hafizurrahman Fatehmahomed
Student Darul Iftaa
Netherlands
Checked and Approved by,
Mufti Ebrahim Desai