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Stones to use in wildlife pond


I am in the process of building a wildlife pond and, as one side will be adjacent to a small seating area, I would like it edged with stones.

My favoured stones, based on size and colour, are the Highland Grey Rockery Stone ( - however the description on this website says these stones are "not fish friendly".

I believe (although I may be wrong) that this is because of the high natural ph levels in the stones.

Does anybody know if the "not fish friendly" warning also applies to wildlife in general, or is it particular to fish - ie could my potential frog, newt etc visitors be harmed if I use these stones?

Many thanks,




  • pansyfacepansyface PEAK DISTRICT DerbyshirePosts: 21,234

    Heavens, another thing we have to worry aboutimage. No idea really. Unless they are very rough and the fish might scratch themselves by accident. My lot sometimes chase each other and I have seen them get scratched that way.

    Why not send the company an email and tell us what they say?

    Apophthegm -  a big word for a small thought.
  • I know what you mean - who thought choosing some edging stones could be made so complicated!

    I sent them an email three days ago, but haven't had a response yet - hence posting on here. I'll give them a few days and then call them (unless someone on here know the answer in the meantime).

    If I do get a definitive answer I will let you know...


  • FairygirlFairygirl west central ScotlandPosts: 49,135

    Could it be that they leach something into the water Col?

    Seems a bit odd though...wouldn't have thought they could damage wildlife in any significant way.

    Probably a Health and Safety issue concocted just to cover themselves...image

    It's a place where beautiful isn't enough of a word....

  • nutcutletnutcutlet PeterboroughPosts: 26,869

    Where do you live Col? Those stones would look really out of place in my fenland plot image

  • Fairygirl - my local garden centre thought it might be something to do with the natural alkalinity of the stones raising the ph level of the water, although he admitted that was an educated guess rather than knowledge.

    Nutcutlet - I'm in Birmingham - the only other natural stone around here is red brick image These stones are the best ones I could find that match the colour of the paved seating area - so hopefully they'll be ok.


  • FairygirlFairygirl west central ScotlandPosts: 49,135

    That was the only thing I could think of Col, but I expect it would have to be a huge amount of rocks and a very tiny pond to make a difference! 

    They look just like the ones I inherited here - which are forming a planting shelf in my new tiny pond...

    I don't have any fish though  image

     Must take a pic of it now that the plants are inimage

    Just a thought - as it's a wildlife pond you're making, you may find the fish eat all the wildlife - unless it's a very big pond and can stand the competition. 

    It's a place where beautiful isn't enough of a word....

  • Thanks Fairygirl - very impressive. Those stones look the very similar to the ones I'm looking to buy.

    Sorry I didn't make it clear - I won't be having any fish in the pond, but I thought if the stones aren't suitable for a fish then it seems possible they they wouldn't be suitable for general wildlife either... (I was rubbish at biology at school - but it seems likely that if something can harm a fish then it would harm a frog as well?)

    Having said that - the website only mentions fish. You'd have thought it would mention other animals if that were the case...

  • FairygirlFairygirl west central ScotlandPosts: 49,135

    I don't think there's much to worry about Col. I've had rocks like these in a few ponds , they were all full of wildlife, and at my last house we had lots of fish too - it was a big pond so plenty of room for everything. image

    I'll let you know if everything dies in this one though...image

    It's a place where beautiful isn't enough of a word....

  • I've had an answer from the supplier of the Highland rockery stones and they have advised that they would not recommend its use in any pond due to "lime or other impurity in the rock that would contaminate the water making it unsuitable for any kind of wildlife".

    They say that 3 out of the 13 types of rock they sell are unsuitable - so it seems that the majority of rock is safe to use, but a sizable minority could cause problems (according to this rock supplier).

    It could be that, as Fairygirl suggests, they are covering themselves from Health & Safety perspective - but as I haven't bought them yet it is probably safer to have a rethink and buy one of the safer types.


  • pansyfacepansyface PEAK DISTRICT DerbyshirePosts: 21,234

    Sounds like a load of cobble(r)s to me.image

    Apophthegm -  a big word for a small thought.
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