Sump basin - large hole, replace?

[Indiana_Homeowner]

Hello,

My home was built in 1977, assume the sump basin is original, size is ~ 18" width x 24" deep. I live in a wooded area and have lots of rust and limestone (calcium) buildup. I've lived here ~ 18 years and had the sump pump replaced 1-2 times and the current pump is 10 years old.

Realizing I was living on borrowed time (by having a 10 year old pump, no battery backup, pump cycles essentially every day unless there is a drought), I decided to replace the pump and put in battery backup.

I was cleaning the basin (first time) and have (what I believe to be) lots of iron ochre and calcium buildup inside the sump basin. I was cleaning using a large flathead screwdriver (gently scrape), shopvac, iron out and vinegar (chemicals separately). Upon cleaning, I noticed a large hole in the bottom of the basin (see attached pics). I don’t believe I created the hole, but not sure if this was intentionally created in 1977. The hole seems rather large, probably 1.5” - 2” long and I think there may be some scouring of the underlying gravel media.

There were some brick pieces in the bottom that I removed during cleaning that could have covered this hole. So basically I’m not sure if the hole has always been there or I created it during cleaning. I know holes in basins are beneficial because they allow water to enter and be pumped out rather than create hydrostatic pressure, however this one seems large and there could be scouring of the underlying gravel media by the pump.

The hole also appears to be directly under the main drain tile inlet, not sure if this is a coincidence.

Should I:

1. Cut a piece of plexiglass and place bricks over the hole to attempt to prevent scouring and not worry about it?
   
2. Hire a contractor to replace the basin?
   
3. Other suggestions?

Regarding #2, prior to discovering the hole, I previously had 3 basement waterproofing/foundation companies come out to estimate removing the existing 18”x24” basin and replace with a 36”x30” basin. My thought was larger volume and plenty of room to install 2 AC pumps (primary & backup) and 1 battery backup pump (3 total pumps, wide basin with plenty of space). Of the 3 companies that came out to give an estimate, no one was willing to do the work. One contractor would only install a TripleSafe Sump Pump System, which I didn’t want (I wanted the larger basin installed), other 2 contractors said they would provide a quote but never did, even after repeat reminder calls from me. After no one wanted to do the work I decided I might as well keep the existing sump basin and change the pump myself.

Besides any recommendations/advice for #1-3 above, any suggestions for competent companies to install a larger sump basin in the Indianapolis, IN area?

Thank you