This post has observed that in some areas of the town, there is a dearth of stp, severely affecting the water qualifty that are emptying into the Laguna lake.
About two decades ago, this post learned some cheap diy stp solution:
1. Water lily absorbs plenty of waste and spoiled matter from the water. That is why drying water lily plants smell bad
2. DIY filtration sedimentation tank filtration:
1. A waterfallls for oxygenation of the water;
2. A sedimentation tank
3. Filter chamber: rocks, gravel, fine sand, even charcoal
UV treats waer
3. This post used this in a project where the effluent of a neighboring subdivision fell, and we got fish at the end of the channel from the chambers.
