Milwaukee MC510 ORP Controller with Mounting Kit, +/- 1000 mV, +/-5 mV Accuracy

Ordered a new mc510. Got a used one. Reads -15 in my reef aquarium. Reads -15 in distilled water.

Excellent controller, extremely accurate... Very reliable for constant use... Make sure to get an extra probe, as the probe develops deposits and needs periodic cleaning... The extra probe keeps things going while the other probe is being cleaned and reconditioned.

I got the meter quickly, set it up and it works as advertised. I think I would buy the same product again only I would be more careful of the particular model. The meter is set up for a permanent place and I would prefer a more portable model.

No way to calibrate the probe. Using ORP standards the reading were not accurate. I do not trust using this item with inaccuracy right out of the box and no way to calibrate the probe! I will be returning this controller. Very disappointed!

EXCELENTE

By the time the meter starts getting updated readings, and the solution mixes, the controller doses a lot more than needed. Especially in my case in a 50 gallon system. The unit needs to have an adjustable dosing length to avoid this.

Excellent product. You're here on time.

I bought two MC510 and MW500 ORP controlers, after two months of testing one probe from each device is not accurate. I mean kill your fish mode. One probe from MC510 and one from MW500. HELP ME!!!!!!!!!!!The failure is actually MC150 controler, one of two I bought. It killed all of my fish!!!!!@!!