Question Concerning Water Hardness dropping dKh

FuglyDragon · Post by **FuglyDragon** » 19 Jul 2005, 12:06

I have a 50 Gal tank set up for warm water Xingu type plecs (2 gold nuggets and a L014 sunshine at present) shareing it with 3 smallish discus a pair of young adult discus and some cardinals.

The water straight out of my tap is 3 degrees dKh ph 6.8(yeah I'm lucky)

temp is 86f no2 0 nh4 0 no3 2-4ppm ph 6.8
Its a planted tank, i have 2 DIY co2 injectors.
External Cannister filter (Eheim 2324)
Hang on filter (Eheim liberty)

It has 2 largeish pieces of driftwood and has been running for almost exactly one year. Water is crystal clear, no sign of tannin staining from the wood.

Liquidoser adds 1ml of plant fertiliser daily

Water changes are about 20% every second day (mainly for the discus)

The fish and plants are all doing very well, two of the discus have even paired off and started spawing on a regular basis.

Annoying thing is the hardness keeps dropping away to 0 over a period of 2-3 days. I have to add JBL Aquadur to get it back to 3-4 so the PH stays stable with the CO2 injection other wise the PH tends to start dropping away at an alarming rate.

Has anyone any idea what could be casuing the hardness to drop like that ? Both Carbonate Hardness and General Hardness seem, to drop at the same rate

Post by **Dinyar** » 19 Jul 2005, 14:16

Your DIY CO2 reacts with the water to form carbonic acid. You can read about this in any article on CO2 injection. Try <www.thekrib.com>. Try buffering with an appropriate amount of crushed coral or dolomite in your canister.

Owch · Post by **Owch** » 12 Aug 2005, 11:16

Sodium Bicarbonate (Baking Soda) or Calcium Carbonate can be added to stabilise pH.

Sodium Bicarbonate will bring up your kH, CO3- ions
Calcium Carbonate will bring up both kH and gH at the same rate. CO3- ions and Ca++ ions

bronzefry · Post by **bronzefry** » 12 Aug 2005, 14:41

I'll trade my water for your water! We'll balance out and have a lovely tank!

Shipping would be a bummer I imagine.

FuglyDragon · Post by **FuglyDragon** » 13 Aug 2005, 21:41

Yeah we are really lucky here. dkh 3 GH 3 Ph 6.8 no chlorine or chloramanes straight from the tap. My discus pair spawn regularly in tap water. Have never ever seen a RO unit for sale in any LFS.