GH increasing major issue

[jwmachon]

Hi all

Got a weird one, I recently changed my scape using original capped tropical aquasoil with Hugo kamishi quartz sand and corbo catfish root and dragonstone
However my GH and TDS is increasing by itself massively tds after a few days 270 from 135
And GH from about 7 to about 14
TDS meter calibrated and test kit cross checked
I'm not overdosing on ferts or feed
co2 in use
apt complete 3

I've soaked some dragonstone and that doesn't appear to be leeching

any suggestions

 

[Wookii]

Dragon stone does tend to be inert, though whether some can contain seams of CaCO3 I'm not sure.

The sand could have some impurities, so worth testing that too.

Failing that, some of the pebbles you've added look a bit suspect and might be worth testing too.

When you do your test, bubble some CO2 in the water during the test - it is the carbonic acid from the CO2 injection that tends to cause the CaCO3 to be dissolved so quickly.

 

[jwmachon]

I think it's the root tabs tbh nutri caps by columbo osomotics

 

[_Maq_]

Dragon stone does tend to be inert

Does it? I'm pretty sure it's a calcite.

 

[MichaelJ]

Dragon stone does tend to be inert, though whether some can contain seams of CaCO3 I'm not sure.

Yes, real / pure Dragon stone should be inert. Dragon is sometimes confused with other stones such as Seiryu stone which are not inert, but the OP's looks like Dragon stone for sure.

A dGH increase from 7 to 14 in just a few days is a massive increase! I would suspect impurities in the rocks (or some of them), the substrate or those random pebbles.

One way to find out is to isolate a sample of each suspects in a bucket with acidic water and test if it raises the dGH over a 24 hour period or so.

I think it's the root tabs tbh nutri caps by columbo osomotics

Im not familiar with the product or its contents, but it would be very unusual for root tabs to contain that much Calcium or Magnesium to raise the dGH 7 degrees in a couple of days.


Cheers,
Michael

 

[LightingBamboozled]

It's such a huge change, that my second suspect (after the meters and tests which you've checked) would be the source water. It would be unusual for it to change that much but I'd definitely double check that before getting heavy into the tank and checking the substrates and hardscape etc.

 

[_Maq_]

You can perform a quick test with vinegar. Just take some samples of your hardscape (sand/gravel, pebbles, rocks) and pour vinegar on it. If you can see bubbles evolving or hear the sound of it, that's what you're searching for.

 

[Andy Pierce]

Can you measure KH? If KH is increasing to the same degree as GH that would be pretty conclusive for a source of calcium carbonate causing the changes. If GH is increasing but KH is not, then you have an issue that won't be resolved by testing materials with vinegar etc.