Sudden rise in High PH, tried everything

[W1368]

I'm a little new to this, the tank was passed onto me but the previous owner had never trimmed the plants or cleaned the gravel. I would say the aquarium is at least 5 years old and the majority of the original fish are still going strong (Rainbows, Neon tetras etc.).

I have been doing basic maintenance up until around a couple of months ago. Recently I've starting getting more into the planting side and found most of my problems was buying poor quality plants from a local aquatic store without actually researching what would be suited for my tank.

Usually within about the past 6-8 weeks (when I actually started trimming more properly and removing debris + using a gravel cleaner during each water change) the PH has gone from a steady and constant 7.5 to 8.0.

I thought the PH should in theory gone down slightly due to less debris from taking out dead leaves etc. I've also recently found that many of the older plants have this very thick cotton wool type material (a pale brown colour) completely covering the roots in the substrate. These I have removed completely.

While I see that the PH is borderline, it does limit my options when choosing new plants. I also wonder why its increased since the water changes are done using water that is 7.5.

After having learnt how to properly trim the different types of plants I'm ready to go full out. The tank is looking very bare at the moment from removing all of the bad quality leaves, especially the ones that were covered in black algae and had black spots.

I've tried all sorts such as lowering the amount of fertilizer and tap water conditioner used, but this hasn't had much effect. Right now there isn't as many plants as before, but this time I'm awaiting delivery from an online company (grown by Tropica) and made sure all the plants are within the PH, DH and temperature range of my tank.

I've heard there are chemicals out there that can lower the PH, but I understand the PH will eventually rise back up to 8 anyway.

Any help would be appreciated to this mystery. There were so many plants that I liked but just couldn't order due to the PH issue. Many thanks.

Using the Tetra Test Kit Laborett:
Tap water PH - 7.5
Aquarium PH - 8
KH - 5dh
N02 - < 3
GH - 13dh
C02 - 1.6 (I understand this may not be accurate as a chart reading using KH and PH)

 

[Tom]

Re: High PH, tried everything

I thought the PH should in theory gone down slightly due to less debris from taking out dead leaves etc

If anything, removing the debris would increase pH rather than decrease it. In a round about way, rotting stuff creates nitric acid which has the potential to lower the pH, to an extent depending on the KH/Alkalinity/Buffering Capacity of the water (which will be pretty high too). The only thing the debris will do is increase your NH3 and NO2 (and NO3) which is bad for fish.

My 2 tanks currently have a pH of 8-8.5, and the plants are growing fine (after a few un-pH-related issues). I wouldn't worry about it at all.

Is your NO2 really at 3? That's pretty high for fish to tolerate. Or did you mean NO3? Any NO2 reading at all is best avoided, but test kits are unreliable.

Tom

 

[W1368]

Hey thanks. I think that explains the sudden increase. Also glad to hear the plants can grow fine in higher pH levels.

My apologies, meant below 0.3mg/l (the test kit won't measure any lower) for NO2.

 

[Dave Spencer]

Usually within about the past 6-8 weeks (when I actually started trimming more properly and removing debris + using a gravel cleaner during each water change) the PH has gone from a steady and constant 7.5 to 8.0.

I like to term things such as this as a non event. Those of us injecting CO2 are probably experiencing swings >1.

Dave.

 

[jm_]

if your worried - try a water change with RO / Di - the PH will take a whack so do it slowly when adding back the water

Monitor it, i would do couple litres and see the impact = PH will also change during the day / night so test same time each day for better consistency etc