Alkalinity falls weeks before pH moves. Field notes on recovering buffer from the anoxic return before buying a chemical, the three chemicals we have actually used, and why how you introduce it matters more than which one you pick.
The standard objection to a water softener is that soft water strips scale off metal pipe and leaves it corroding. In a Cebu building the risers are PPR, so the mechanism has nothing to act on ā and the real saturation-index exposure is concrete, not pipe.
On one meat plant we kept the media moving in the first aeration tank and hung rope bundles in the second. Field notes on where we use MBBR, where we use FBBR-style fixed-film media, and the one result we cannot explain.
Sizing a dosing pump for four grease traps and 400 mL a day: why the smallest industrial pump is twenty-two times too big, why metering by time fixes that, why we threw out the solenoid-valve architecture, and why the tubing chose the pump.
Why we left the enzymes out of our grease trap conditioner, why the digesting culture carries them instead, and why we rejected a powder on engineering grounds rather than manufacturing ones.
Two design-only quotations, fifty times apart in plant size, came out about 1.5x apart in fee. Why delivering a sealed design set is near-flat work, what the external seal now costs, why a percentage of the works is the wrong shape, and the unflattering part: neither quotation sold.
Where IWSI's free advice stops and the invoice starts ā tank volumes, process flow and an unsigned layout for nothing; sealed drawings, engineers' time and site attendance paid. Field notes on a line that moved this year.
A client had a routine DENR inspection and asked us to file a corrective action plan. Nothing had been cited. Field notes on establishing what the event actually is, what a submission should say, and the things we put in writing anyway.
An owner sent us both quotations and asked us to explain the gap. Most of it was scope, not margin ā and we will not tell him the cheap plant must be imported junk.
A small job came back from our own drafting as a six-page itemised quotation. Here is why we cut it to two pages and one price, what we never cut at any length, and the times we got it wrong in the other direction.
