Calling all structural engineers... Is this stand going to fail? What can i do?

[tang named junkyard]

I have a 100 gallon reef with lots of rock. I picked up the stand and tank used a while back. 3-4 years. I thought a couple things in the back looked weak so I put some 1x4 oak bracing in. 2 in the middle supports and one in the left rear corner by the water drain. The guy before obviously modified the base by cutting out a hole for the inlet. I really don't want to drain the tank but I don't like the slight bow in the back left. I'm thinking about removing the lower sump and drilling a couple holes and putting in a lag bolt with a flat washer to suck it together? Bad idea. Here are some pics.

Here's the left rear. Notice the bottom is bowed out away from the 1x4 oak support I put in last year. This is the area I'm thinking of putting a lag bolt in to squeeze it togetherbut I don't want it to fail. Will that help make it stronger.
http://i13.photobucket.com/albums/a294/imracin68j/IMG_0800_zps1n2ojsd1.jpg

Here you can see where he moved the 2x4 from the corner to put the inlet in. The 2x4 looks split down the middle. I'm not sure if it's glued together but it looks sketchy. He moved it to the center. I'm thinking of replacing this. Should I screw it or glue it into the side or is that bad?
http://i13.photobucket.com/albums/a294/imracin68j/IMG_0798_zpsrbdmcpda.jpg

[GimpyFin]

The important thing is that weight from the top is transferred down to the floor along the edges where the tank rests. If you have that support similar to the attached picture, it's probably ok. The 1x4 piece you added might stabilize that existing piece a little if you took a few screws and tied them together, but it doesn't appear to be adding any load bearing support since it's attached to the side underneath and not directly supporting the top.



http://i299.photobucket.com/albums/mm289/RocketEngineer/StandTemplate.jpg