Help - newt disaster

[welly101]

Can anyone offer some advice - I have had a wildlife pond for many years but had to re-line it a couple of weeks ago after the liner got punctured - I suspect one of the local herons who visit us occasionally. Got the new liner in and put some tap water in and straight away a dozen of our smooth newts, plus a couple of frogs dived into the new pool. All went well until four days later I found all the newts dead. The frogs have made themselves scarce. I used cement to pave aound the pond and a lot of snots got in the pool. Could it be this which killed them ? Any advice would be gratefully recieved. I still have some juveniles in the buckets I used to keep the plants in while the re-lining was done, and I don't want to put them in the pond if there is a risk of another tragedy.

[Kayleigh]

Did you treat the cement with a sealant as it can leach chemicals into the water..
I don't think it would be the tap water that killed them.

[diggleken]

Agree with Kayleigh - and the cement on its own even without a chemical sealant or plasticiser etc isnt good - partic if there was a lot dropped in.
If its that, the pool should settle down, but could be a few weeks , maybe better though to empty again and put fresh water in, if tap, leave for a few days to be safer.
Use the buckets as temp storage for a couple of days?
Ken

[crazylilthing]

Originally Posted by welly101

Could it be this which killed them

Agree with other posters. Cement is strongly alkaline. You could try filling the pond, leaving it for 24 hours and then draining it before filling it with fresh water, for several cycles.

However I don't think the cement will settle down for a bit longer than this. You may want to leave the last lot of water in there for a week before draining and starting again. It's a lot of work but that's what I'd do.

[welly101]

Thanks for all the replies. The good news is that we now have some live and active newts back in the pond and none have died so far. I'm hoping that the chemical balance of the water has now been restored and all will be well. The old plants are back in and they too look fine. Just out of interest, I think it may well have been the cement. When we relined we only threequarters filled the pond with tap water. The cementing around the edge then began but already the newts, fatally, had returned. We then had several torrential rain storms which raised the water level up to and over the new cement. I had covered up the fresh mortar but the storms were quite violent and rain water had in places washed over the pointing. The cementing was around some old re-cycled stone sets and so it may have been either the uncured mortar suddenly leeching alkalinity into the water or even some other contaminant already on the sets. The only lesson to be learned from all this is don't cement around a wildlife pond - socially unacceptable in suburbia though ! And be picky about what re-cycled building materials you might use.