Flush force slowing

[jaybird]

Flushing action in our 2 toilets is beginning to slow, sometimes requiring a 2nd flush.

I have checked the rim holes, and they are open.

Last May when I had a no-flush situation, I used a responder's suggestion regarding muriatic acid, and it was very successful.

I think another rim cleaning may be needed. Are there less drastic methods than MA that I can use to do this?

The siphon seems to be clear and open.

All suggestions are appreciated.

[dc_homeplumber]

If your rim holes are completely clear, there can also be mineral build-up in the rim channel and/or the trap that can hinder the flush. About the only good way (that I'm aware of) to eliminate those problems is with muriatic acid. I know, it is FOUL. All this, of course, is barring any main drain issues.

[Cass]

If you are getting mineral buildup you may need a softner.

[v_phillips]

Phosphoric acid works well. It's not as caustic as muriatic acid and does not emit such dangerous fumes. You would still use it with caution though. You definitely don't want it in your eyes and you don't need it on your skin. The fumes can irritate your nose, throat, and lungs if you inhale them enough.

You can find phosphoric acid at Home Depot in the flooring section because it's commonly used to remove the haze sometimes left over after grouting a tile floor. It's a red liquid in a silver-gray plastic jug. It's also sold as a rust remover, in which case it may be greenish, more expensive, and bottled with a different label.

[hj]

My experience has been that it is also not as effective as MA for removing the scale build up.

[jaybird]

A big Thank You to all repliers.

The phosphoric acid idea is going into a permanent file, so that I don't forget it.

I have corrected the situation for now, by raising the water level slightly above the mark level ( but still well below overflow ), and normal flush is back.