Air bubbles coming out of returns in DT, how do I fix?

Just like the titles states.  I put in a larger return pump I got from Bud.  Looks like a Reeflo Dart.  Not sure on its output though.  I have the plumbing a tad goofy.  I have 2" return coming off of the pump that splits to 2 - 2" Ts.  One the Ts points up and then reduces to 1" before heading into a 10 Gallon tank where I will be putting mandgroves here in a few weeks.  Then the T connects to another T where I am planning to add an ATS if I ever get it built to help with algae growth.  Then the 2nd T reduces to 1" which then heads to my DT where the 1" return breaks to 2 - 1" Returns.
Now I have the 2" Ball Valve that is straight off the pump cranked on Full.  The Ball Valve for the Mandgrove tank and ATS are currently off.  To keep the bubbles from entering the DT I have the DT Ball Valve at right around 1/3 on.  This is killing the flow back into the tank where it has lowered my tank level.  If I give it anymore than that I get the air bubbles shown in the video located here.
I've gone back thru my plumbing and sealed all the joints from the outside with more PVC cement making sure I don't have an air leak. The only other thing I can think of is that there is something wrong with the pump but the pump runs smooth and is quiet to the point you cant even hear it when you sit beside it.
Anyone got any ideas or something I could try to get this stopped?  I am home all day today and home mornings if anyone wants to stop by and take a look at the mess I have.  My cell # is (319) 361 - 8306.

 

Well... I didnt know what I was doing when I plumbed my drain almost 8 months ago so I have 2 1" drains that go to a 2" T and then down a 2" PVC run to the sump. Just a single drain line. So without replumbing my drain, which my finacee will kill me if I need to that, is there any way of fixing my issue? Thought about using some screen like Bud did at the dentist office but I dont see any bubbles in the sump.

 

video is a 3gp file taken with my phone. you'll need quick time to watch it.

I resealed all the return joints as well. (forgot to mention that in first post). The returns might be a tad high but they are fully submerged under the water of my DT. I do have a T off spot where I could have water run back to the sump. It is suppose to be my ATS connection. I've ran that spot open half way and the main line to the DT on full and it makes the water bubbles worse.

Keep the suggestions coming. We'll crack the case sooner or later.

 

new video link - here

 

Working on getting the new video tour uploaded as well speak.

From tank to the pump is 2". You'll see the massive ball valve that was used by the previous owner in the video here shortly.

 

video tour of DT and plumbing - here

 

The smaller pump was 1" from the sump to the pump then 1" out to the DT. I broken the 2" return to 1" on this pump as I was told I could easily break off and run other equipment. Starting to wonder if I should've ran 2" return all the way to the tank then to my 1" returns.

 

I was running 1500GPH then that pump crapped out so I went to a 900GPH to get me by for a little bit. Then Bud gave me this one. I have no idea what its output it. Guessing close to 2000GPH. I was looking to get back to 1500 at least if not to 1800 GPH. So is there no way to fix this without replumbing?

 

hmmm... not sure what else to do here. Anyone else got something I could try without a massive rebuild?

 

and if they are in suspension how do I get rid of them?

 

So we're now thinking I have extermely high back pressure that is causing the issue. Never would've guessed the pressure to be that high. Let me see what happens. Hope I dont flood the place lol