This is the 1st. Homekit that I made few years back. It still holding fine, lack of care doesn't stop it from operating.
This set is at a relative place in the same neighbourhood. It is here for about 2 years plus and I can't recall that the water changed.
Tilapia is a tough fish and its survive without much caring. BTW that water jetting out from the feed pipe is from my "Saddle Valve" design.
Good size to make breeder and they are in good health.
This set use pebbles not LECA, the rack was made from thick hollow square tube and it is a good example that this set can last a long time.