Water pH, hardness, and nitrates for java ferns and anubias plants

[Jim Fox]

I am on well water that I soften due to water hardness of around 60 grain and it has a pH out of the tap of 7.2 to 7.4 but after a 30% water change and waiting a day or so, the aquarium pH is 8.2 with nitrates below 30 ppm.  I have java ferns and some anubias plants.  For fish, mostly a variety of tetras, a 7 inch BN pleco, 3 albino corydoras, and a single kissing Gourami.  All the fish have been with me for over a year, some as much as 4-5 years.  I started plants about a year ago and use Easy Green.  The substrate is just typical aquarium stones and I have 2 large pieces of driftwood that have been in the aquarium for years.  My question is, what is causing my pH to stay up at the 8.2 range?  Second, my Anubia plants are growing but all the leaves seem to have a grey/blackish beard around their edges.  I attached a picture.  Just curious as to what this might be and any suggestions for preventing.  The plants keep putting out new leaves but after a month or so get this grey beard.  Is it algae?

[nabokovfan87]

It feels like you snuck in and took a photo of my anubias tank. 😂

 

On 7/7/2022 at 6:37 PM, Jim Fox said:

My question is, what is causing my pH to stay up at the 8.2 range?

Good question.

Before we get there can you run a test?
1.  Take a sample of tap water, test everything you can.
2.  Aerate that sample with an airstone for 24 hours and re-test.
3.  Compare results from #2 after off-gassing to your tank in question.  This is what we'd expect the PH/KH/GH to be after water changes.

On 7/7/2022 at 6:37 PM, Jim Fox said:

The substrate is just typical aquarium stones and I have 2 large pieces of driftwood that have been in the aquarium for years. 

By chance, do you have a lot of shells or rocks with calcium stripes in the tank?  Maybe unknowingly the substrate or hardscape is buffering the water?  Do any of the stones on the substrate feel like plaster?

On 7/7/2022 at 6:37 PM, Jim Fox said:

The plants keep putting out new leaves but after a month or so get this grey beard.  Is it algae?

It looks like you have both staghorn and black beard algae.

[Seattle_Aquarist]

Hi @Jim Fox

"I am on well water that I soften"

Softened water can be a problem with a planted tank.  How are you softening the water?  If you are using a resin water softener what happens is the resin 'strips' the calcium and magnesium from the water replacing it with either sodium or potassium.  Excessive sodium or potassium can adversely effect plant growth.  Instead of using a water softener a much better method is to use RO water mixed with your 'normal' well water to achieve a moderate water softness. -Roy

[BradfordAquatics]

Do you have anything like limestone rocks, texas holey rock, crushed coral, etc. in there?

[Jim Fox]

I suspect that the substrate is buffering the water but not sure what to replace it with from the aquarium store.  Any suggestions?  If what I have is staghorn and/or black beard algae, what recommendations would folks make to slowly remove?