toilet blue blocks and plastic cisterns

[what..the?]

I do like using blue blocks but I heard that a substance in the blocks corrodes plastic seals within the cistern is this true?

Also I have seen a toilet I would like to buy (purely because it has a large seating area) but it is a one piece cistern which is supposed to all modern, it means there is no lid on top, instead you unscrew the push button on top and pull the cistern cover towards you, underneath is a plastic container as a hidden cistern. The plastic cistern is very small and compact. I have been told these plastic cisterns are used in the built in cistern toilets. Has anyone got a plastic cistern, or heard of plastic cistern, whats the life span, quality like?

Thanks

[what..the?]

mixed reviews?

http://answers.yahoo....20080320091531AAH8fBf

[chas2008]

i have a plastic cistern, pretty bomb proof and i have never heard of seals going other than age/wear & tear.I bought it as the ceramic blue one cracked, price of a replacement £200+ as its not a popular colour anymore the solution was a plastic one £22.95 and spray it blue !! job done

I actually have an above ground pool with loads of seals in the pump we run neat chlorine through it everyday in the summer, cant get much more corrosive than that , i check them every year and they are as good as the day i bought the pool 11 years ago

[The Builder]

I've never come across any problem with the blue blocks, Mrs What. In fact, I've seen plenty of fifty year old cisterns with them in. I can't say it's ever been an issue. I guess someone had a leak from other causes, and just attributed it to the blocks. I do find people often become quite desperate looking for causes.
"Back to wall" WC pans have been around for many years. I've never heard of, or seen any problems with them other than the usual wear and tear, ballvalve replacement etc.

Tick them off your worry list ;o)))

[what..the?]

Thanks for the comments. Well it's the manufacturer that said this on the phone to my supplier, it might void any guarantee/warrant.

[Charnwood_Fox]

Most manufacturers of plastic cisterns say NOT to use blue blocks. They can discolour the plastic, leaching through to the outside surface. I have seen this discolouration. A housing association I supply now pays £20 extra for a better quality cistern to try to aleviate the discolouration problem (Dudley Trishell at over £60 each), although Dudley put stickers in their plastic cisterns, warning against the use of blue blocks.

[Charnwood_Fox]

Corroding seals is a new one on me.

Most plastic cistern manufacturers say NOT to use blue blocks. They discolour the plastic, right through to the surface. I've seen this.

A housing association I supply changed to a more expensive plastic cistern due to it being less susceptible to discolouration, although the manufacturer - Thomas Dudley - puts stickers in all of their cisterns warning of the problem and stating that using blue blocks invalidates the guarantee.

I'd be more inclined to go for a colourless block, or use a toilet rim type.

[Charnwood_Fox]

Whoops, double post. I thought I'd deleted the first one. Sorry!