Ph 4.7 and fresh cut driftwood

[aqua_che_scapes]

I have been trying to stabilize a 5 gallon shrimp tank that has plants, moss, Ada Amazonia, and spiderwood for over two months.  

 

the issue that is happening that I wanted to atleast inform people about or get feedback on is this:

 

four days ago my ph had been a consistent 6.2 for a few weeks and the water was finally clearing up from a long term bacteria bloom but I decided that all the branches sticking out of the water weren’t something I wanted in my shrimp tank.  It made maintenance and scraping the glass very difficult and my plants didn’t have much room to grow and I knew suicidal shrimp would crawl out.  I took the spiderwood out of the tank and used yard clippers to cut off all the vertical sticks and pieces creating many small exposed stumps which I then attached buce and mosses to.  After filling the tank back up with bee shrimp gh + RODI water (with tds 150 and ph 6.4) within a day the ph dropped to 5.8 and stayed a few days which was fine with me.  I did another 50% water change several days later to remove a lot of debris in the water from spiderwood fungus that was floating around the tank (using the same TDS 150 ph 6.4 RODI water) and the ph started to rapidly drop over the next few hours all the way down to 4.7 and counting!  The KH is near 0 and GH is around 5-7.

 

I grabbed baking soda ASAP and raised the tank back to ph 6.5 and it has stayed that way for 24 hours now.  But my main thought was the fresh cut spiderwood was the only thing I have changed to this tank besides water changes.  

 

Before I cut the wood I realized the possibility of more white fungus which I was prepared to deal with but a total ph crash I had not predicted since spiderwood is pretty neutral and doesn’t leach much tannins.  The Ada Amazonia I am using shouldn’t buffer the ph that low.  I aged it in a bucket for a few months before using it in this scape.  And my other shrimp tank has the same Amazonia but stays in the ph 6 range and doesn’t crash. Both tanks are treated the same,  only difference was the spiderwood.  

 

I mostly just wanted to warn anybody thinking about trimming their spiderwood in their tank and maybe get some thoughts or experiences shared.  I had done lots of forum searches on cutting/trimming driftwood before attempting the trim and didn’t see anything about this.  I wanted to put it out there.  

[aqua_che_scapes]

To experiment I will be taking one of the branches of spiderwood I trimmed off and placing it in an isolated plastic container of the same water values and checking the ph on it to see if I can replicate the crash.  

[EricM]

baking soda will only be a short-term fix,  the soil will absorb the KH and it will drop again.   Are you sure your PH test kit tests that low?

 

[aqua_che_scapes]

Ok I wasn’t sure how long the baking soda would last in the Amazonia filled tank.  I’ve been monitoring it closely to make sure it doesn’t drop again.  So far it’s a consistent 6.5 since I added the soda a day ago.    I’d rather not have the soda in there cause I don’t want to exhaust my substrate faster but I really didn’t know what else to do.  I have some struggling plants and mosses in there and it killed my one Amano shrimp I had in there.  I got him out fast but he didn’t last long after that in my other tank.  

 

I use a calibrated digital ph probe meter that can read as far high or low as the ph can go so it is handy for monitoring soft water.  I check the ph on my more neutral ph tanks to make sure the probe matches as close to the API test kit results as I can get.  It might be .2-.5 off but it is pretty accurate enough.