Suitability of ph 7 (using Gex soil) for CRS tank

[catohcat]

I'm setting up a CRS tank. At the moment I have been leaving the tank empty with plants & an otto only for two weeks. I do constant tests during these period. I found out that my tap water is fixed at pH = 7.5. Therefore my Gex soils can only stabilize the tank down to pH=6.9 - 7.0.

I understand that CRS need a pH of 6.5 to thrive... so is there any method to lower down the pH to 6.5 without any harm to the CRS and keep the pH stable at that value?

My tank spec is as followed:
+ 1ft tank ~ 12Litters
+ 3cm thick of Gex soil + a thin layer of ADA Power Sand Special.
+ Under gravel filter + Eden 501.
+ CO2: nutrafin CO2 - one bubble per 3 seconds.
+ pH: 7.0
+ Nitrite : 0.25 mg/L (ppm)
+ Ammonia : 1.0 mg/L (ppm)
+ GH : 1 degree.

Thanks all bros in advanced

[genes]

I believe GEX soil may not necessarily reduce the pH of the water. Think on the package its written in japanase something like "maintain pH". Some alternatives to lower pH naturally would be ADAsoil or using peat. You can get sera superpeat off the shelves. However, i know of people who have success with keeping CRS in both GEX and ADAsoil. So you may not need to add anything after all. But i let the CRS experts here decide on that.

[Razorblade]

I use fresh lime juice to bring down the PH

[catohcat]

Razorblade, and your CRS still survive? May I ask draftly how much lime juice you used for 1L of water?

(Edit: catohcat, please kindly refrain from using SMS shortforms, otherwise you will find your posts go missing every now and then! Thanks.)

[Razorblade]

I mix it in a container for aging the water a little at a time and measure with ph pen until the desire value, no problem so far, but don't hold me for that, use at your own risk

A friend of mine almost got all his CRS wipe out after using some ph down chemical, but it could be an isolated case or the CRS are simply too sensitive to chemicals.

Cheers,

[catohcat]

so besides lime juice is there any other ways that CRS hobbyists lower down the pH?