Plumbing T split question

[Levinson]

If I plumbed like the diagram below, would it be hard for the water to be pushed upwards through the vertical T split?

I plan on making Donnovan's Nitrate Destroyer and placing it inside the tank so I need a flow going into the DND but I'm not sure if I could T off the return plumbing (like the picture above) or if I should just get a separate small pump for it. The flow rate needed for this is very low but it should be able to pump the water high enough (about 15cm above the water surface?). I don't have much knowledge in physics and I have no idea how viable or not this is with the other end of the horizontal pipe open.
The best way would be to actually try it but I wanted to get any feedback I can before I get the stuff needed.
The picture below is a very simplified image of how it might be plumbed.

 

[Rollins]

Yes, a T should work great for that kind of flow. I have 3 Ts off my return, all plumbed with a 1/2” push lock tubing connect. Then a mur-loc ball valve so you can adjust the flow down as slow or fast as needed. I run 2 small carbon canisters and an algae scrubber from my return

 

[Rollins]

Some pics for reference

 

[Levinson]

Yes, a T should work great for that kind of flow. I have 3 Ts off my return, all plumbed with a 1/2” push lock tubing connect. Then a mur-loc ball valve so you can adjust the flow down as slow or fast as needed. I run 2 small carbon canisters and an algae scrubber from my return

Thanks for the feedback. Your sump setup looks great btw.

 

[BZOFIQ]

You should put a valve after the T to control the amount of flow; without it the top of the T may receive very little flow depending on the back pressure

 

[Levinson]

You should put a valve after the T to control the amount of flow; without it the top of the T may receive very little flow depending on the back pressure

Yeah, that was planned but I didn't bother to put it in the picture.
Edit: sorry I read it wrong. I see what you mean now. Yes, I guess that can be done.

 

[Levinson]

I ended up trying a method that is different from the drawing and it failed but found a new setup that works. I feel so dumb not having thought of it before. Pushing water up in this kind of setting was much harder and required much more force than I had expected. A ball valve to control the open end like BZOFIQ had suggested would make it easier but I did it without a valve.
This is the one that didn't work. Even with the pump at 100% power, the water just wouldn't go up.

and this is the one that worked. I really should have thought of this first! But even with this, the pump power needed to be increased more than I had thought for it to be able to push the water up which was quite a surprise for me.

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