Need help with phosphate and nitrate

[ghostfacedclown]

Hi everyone, Basically I left testing for 2 weeks and had a mag/cal and alk drop so I’ve just fixed that then i was looking and in the last 2 days one of my clowns disappeared fully with no trace, (the tanks only 4 months old) so I moved all the rocks looking for him, now my phosphate has gone up to 0.6 and my nitrate over 50, my tank is 200l and I’m in the middle of doing a 50l water change and I was going to get some Rowa phos tomorrow, any advice would help

 

[Auroraz]

have you checked the sump?
my clown once took a trip to the sump through the overflow pipe

 

[ghostfacedclown]

have you checked the sump?
my clown once took a trip to the sump through the overflow pipe

Yeah checked the sump, I have a lid and there’s no bones anywhere, god knows what happened but my cleanup crew must have been hungry