Lowering GH and KH

[On_a_dishy]

Hello!
Jarvis is my betta and he has been glass surfing a lot. It's not his reflection, because he doesn't flare. It's not the water flow or the lights. He lives in a 34l tank and his only companions are two African Dwarf Frogs who ignore him (and he ignores them).
He has had a recent succession of water changes thanks to my over-enthusiastic cleaning of his tank which destroyed a load of bacteria. I'm nearly at the end of the cycling now.
I was lowering his water hardness through mopani wood and almond leaf - these worked moderately well and lowered the pH to 6.8, and the carbonate hardness to 6d (my tap water pH is 7.6, carbonate hardness is 10d). The GH has read >14d for both.
Anyway, because of Jarvis's many water changes (I think), the pH is back up to 7.6, the GH seems to have gone up to >21d and the carbonate hardness is a huge 15-20d.
Nitrite is 0 and nitrate is 25mg/L. Chlorine is 0.
Could the water hardness be causing Jarvis to glass surf, or could there be another reason?

 

[Colin_T]

Glass surfing is caused by boredom and has nothing to do with pH, GH or KH. Your fish wants to explore and see new things. It can't so swims back and forth against a clear surface that it can't comprehend. Imagine being put into a glass box and not knowing what glass is. You could feel something there but can't see it. What is it?

Growing algae on the back and sides of the tank can help reduce this. Having plants in the tank can also help reduce it. Getting him a girlfriend might help too but if he doesn't like her they might fight.

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Water changes don't get rid of beneficial filter bacteria. They do help to reduce the number of disease organisms in the water column but do not affect bacteria living in/ on hard surfaces like the filter media.

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A pH of 7.6 is fine for Bettas as long as they aren't wild caught and the common Siamese fighting fish is not wild caught.

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The only way to reduce the GH and KH is to use distilled or reverse osmosis (R/O) water mixed with the tap water.

The KH is used to stabilise the pH and stop it dropping. When acids are in the water, they get neutralised by the KH. When enough acids use up the KH, the pH can drop suddenly. You want to avoid sudden fluctuations in pH.

 

[On_a_dishy]

Thank you for this - it explains a lot I'm glad the problem isn't the water.
Jarvis has a lovely piece of gnarly mopani wood, lots of 'moss' balls and a large almond leaf in there, all of which he stays away from, preferring to swim up the glass. There are 2 plants in there, too, but they are not very big yet.
I have an algae wafer that I'll stick on the glass for him. Are there any betta ladies that I can 'hire'? Is this a thing? What happens if I get him a girlfriend who he doesn't like? He's so brilliant I want to make him happy!

 

[Naughts]

I wonder what has caused your GH to rise higher than the tap water? What substrate are you using? Do you have any reactive rocks?

 

[On_a_dishy]

I've just tested again and Jarvis's GH is the same as the tapwater - somewhere between >14 and >21. But if I had to judge between the colours I would still edge towards Jarvis's water being harder - which is bizarre. In fact as I look at the strips now, there's very little difference in any of the readings (except for chlorine). I use the eSHa test strips.
I did a 50% water change for him today because I bought him with nipped fins (which one of the fishforum folk pointed out) so I'm taking care to keep his tank clean. In it there are 2 ADFs, a gnarly piece of mopani wood, an almond leaf, several moss balls, 2 young plants (I don't know their names) and normal gravel substrate.
Now I'm wondering how to relieve Jarvis's boredom! One site suggests a ping-pong ball...