low flow in overflow

[PrettyFishies]

I rescued a clown from my overflow and in the process some crabs got into the plumbing. I had to take things apart to remove them and now the flow is like 60% slower. I tested the water through the plumbing without the stabdpipe and it gushed at full velocity, so it's the standpipe. I cleaned it out and there's nothing I can see. What could this be?

 

[Toffee]

When u put everything back, did u adjusted the water level？some overflow box can adjust the height which will dictate the Amount of water flowing in.

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