Mark Nellesen Plumbing & Water Treatment

The "Original" Mark, the former owner of Mark's Plumbing™

Full Service Plumbing for Your Home or Business

45 years experience ✯ Quality Workmanship ✯ Lowest Prices
(714) 345-7456

General Repairs

$10 OFF
Service Call

Bathroom and Kitchen Remodeling

With my years of experience, I can transform your bath or kitchen. I can save you money as well, by passing on my wholesale discount!

Drain and Sewer Cleaning

I can clean out all drains, and I have other, less-expensive options to prevent future stoppage problems. I'll install two-way clean outs for future access if desired. And I'll replace bad sections of drain pipes or the entire sewer line if necessary.


We can fix a small leak or re-pipe your entire home. We can replace all pipes with crosslinked polyethylene (PEX) pipe such as Uponor's AquaPEX®, which has a 25-year guarantee. PEX is flexible tubing with a memory and uses a special expansion tool so there are no restrictions in flow and also no clamps that will leak eventually.

Manifolds are common additions to PEX systems, functioning as the "hub" or centralized location for all of the PEX lines. In plumbing systems, there may be one centralized manifold (known as a "Home Run system") or multiple smaller manifolds distributed throughout the residence. Manifolds act as the distribution points from which loops run.

The Uponor company's North American headquarters are located in Apple Valley, Minnesota. The company was originally known as Wirsbo and was founded in 1620, forging high-quality steel and weapons for the King of Sweden.

Water Heaters

We can furnish and install both traditional tank-type water heaters and tank-less water heaters (with rebates). A tank-less water heater is generally considered more energy efficient because it heats water only as it is needed. When the tap is turned on, the heater goes to work and supplies continuous hot water. They have a life expectancy of 20+ years, which can be three times the life of the traditional tank style. They may reduce water heating bills by as much as 40%, and they never run out of hot water. A tank-less water heater also requires less space and can hang on a wall.

$50 OFF
Water Heater

Installation We can install a new tank-less water heater just outside your existing water heater on the exterior wall. We can also use existing vent pipe and run new tank-less venting up through old vent. We can use a 1/2" gas line in many cases to prevent running larger 3/4" gas line at additional cost.

This has proven to be very successful and will save you water, energy and money. We offer a huge savings on what most tank-less water heaters cost. Navien, Rinnai, Noritz and commonly-known brands of tank-less water heater, and many other brands are available for installation as well.

Water Softeners

My water softener is like a workhorse that does not break down—or have computer problems. It's similar to your water meter. It just calculates the gallons used and regenerates on demand. It uses a mechanical meter, not a computer. This is better in most cases.

I've been installing the same unit since 1985, and they are still installed and working fine! It uses less salt than other units, and has a 20+ gallons/minute flow rate instead of 12 gallons/minute like many units out there like GE, Sears, or Eco.

In cases when a computer-driven softener is called for, I sell and install Fleck equipment. Fleck is a newer-style computerized system that is better than any other computerized water softener.

Whole House Filtration and Chemical Removal System

I am a certified Water Purification Specialist. Call me out for a "water analysis" and consultation and free estimate.

I can provide whole-house filtration and chemical-removal systems that are as good as the expensive Life SourceĀ® systems. They also can be installed in conjunction with a "scale reducer unit" that does not use salt.

$25 OFF
Reverse Osmosis System

$150 OFF
Soft Water & Reverse Osmosis Installed Together

I'd Love To Hear From You!

Call or Text me at (714) 345-7456