Things affect pH?

[albash]

Require some feedback on certain things that can cause pH swing - please advise so I can throw them away. I have been battling on pH swing, nitrate and ammonia for last 6 weeks - tired

 

I've read somewhere that rock can cause pH spike - is that true (pict 3)? If so, that explains of pH spike of my tank. Tank has fluval substrate approx 4-5cm thick (first picture)

 

Can I ask if rock at pict 2 cause pH swing?

 

Please identify the rock at pict 1. Friend gave it to me and he doesn't know what it is.

 

Thanks.

Edited January 16, 2015 by albash

[steffiev]

Try testing it with vinegar?
Put a few drops of vinegar on each rock. If there is a reaction (bubbling), then don't put it in the tank.

[inverted]

Good advise about vinegar test....Even better remove everything but plants shrimp and water from tank and see if your ph stabilises. If not look at your substrate. Im no geologist ....but if you don't know what the rock is .you should take it out ...for now.

Edited January 16, 2015 by inverted

[Squiggle]

Any kind of rock with carbonate in it will increase pH, without being able to test it or the knowledge to properly identify then, the best way is the one already mentioned, remove everything & test from there.

[albash]

Thanks for input.

 

Luckily I haven't use rock at 1st. Will take out all rocks but with another issue that I accidentally mix those small rocks with substrate. Now it will be a painstaking to take them out 

[northboy]

Knowing where you live would help as water is different every where and some one close to you may be able to help.

 

To give you an idea I live in Cairns and I use Coral in every tank, because my water is like RO straight from the tap KH 0  GH 0

 

If your water is hard you have to be careful about what you put in.

 

Bob