Home > Home & Garden > Toilets > Toto Aquia CST416M

Toto Aquia CST416M Review

By: Kelly Burgess on September 12, 2017

Bottom Line

The Toto Aquia CST416M dual-flush toilet earns some of the highest ratings we found for its performance in flushing both liquid and solid waste.


  • Compact
  • WaterSense certified
  • Solid waste flush option cleans bowl well
  • Skirted design is easy to clean


  • Challenging installation
  • Learning curve for optimal flushing
Our Analysis

Breaking it down


Dual flush; two piece toilet. The Toto Aquia CST416M is a two-piece, dual flush toilet with a gravity-assisted, tower-flush operation. The Aquia is WaterSense certified to reduce water consumption. It features a two-button, pushbutton flush operation, one for solid waste, the other for liquid waste. It's WaterSense certified. It uses pushbuttons located on the top of the tank rather than the traditional trip lever on the side. The toilet seat is not included, but the Aquia is compatible with a wide range of seat options.


A bit of a learning curve. The Toto Aquia's Maximum Performance (MaP) score is only 500 out of a possible 1,000, and it does not clean the bowl of solid waste as efficiently as standard, single flush toilets in professional tests. However, owners say that they love the performance of the Toto Aquia CST416M once they get the hang of how long to hold down the buttons. Unlike a traditional lever flush toilet, you can't just push and go, users say you have to hold the solid waste button down for as much as 5 seconds to get a good, complete flush and total bowl-cleaning performance. Even then, there are plenty of complaints that the Aquia does not clean the bowl of solid waste and has to be flushed a second time. However, the vast majority are pleased, especially since the solid waste option uses 1.6 gpf, but the liquid waste option only .9 gpf and water-conscious users prefer that alternative to a single flush toilet.


A challenge to install for some, but easy to clean. The skirted, concealed trapway design of the Toto Aquia CST416M is frequently praised by owners for being both modern-looking and easy to clean. Quite a few reviewers say the Aquia is more difficult to install than most standard toilets; but many others disagree, saying they had no issues at all. If you are concerned about that, it may be worth hiring a plumber to avoid any possible issues, although Toto's customer service is reported as extremely helpful for those who have questions or problems. The Aquia CST416M has a smaller footprint than most toilets, making it an excellent choice for a smaller space. Its 15.25 inch bowl height does not meet ADA standards. The Toto Aquia CST416M comes in five colors.

Recently Updated
Toilets buying guide

What every best Toilets has:

  • Low water consumption.
  • The right height.
  • Wide flush valves.

Read More »

Learn More »