Water Changes To Bring Down High Ph

Situation:
I have a (trying to be heavily) planted 37g aquarium that I made a concrete backdrop for. I cured the backdrop for a few weeks with vinegar in the tap water (naturally between 6.8 and 7.0) to speed things up. This caused a precipitate and some still high but not crazy readings. Then I cured it for another few weeks with a large piece of manzanita driftwood, which released tannins and stained the concrete (it actually looks really cool), and brought the overall pH down to the 7.6-7.8 range which was great for my endler. A few more water changes over the next few weeks, and things were stabled and it looked good to go. I put in my soil/sand substrate, and capped with a little crushed coral to add some dissolved solids (my water is very sterile since it's nearly pure rainwater). Tested things daily for the first few weeks after I added endler and it looked great. Then I stopped testing as frequently, and didn't test at all last Thursday because I did a massive (75% or so) water change while I messed around with adding more plants.

I lost a ramshorn snail in my tank the other day, and then yesterday I lost an endler. I don't know that it has anything to do with anything (the endler had been acting odd for a long time), other than I took my parameters yesterday and had 0 ammonia, 0 nitrites, 20 nitrates, and a p.H of 8.6, which is higher than I've ever seen in the two months this tank has been up and running. I'm worried that my backdrop is leeching again. I'm going to do a water change today (25%) and add some Indian Almond Leaves. Should I do daily water changes until it's back down in the healthy range, since my water is naturally neutral-acidic? Or is there a better way? And how fast can I do this without risking the rest of the fish (who are still acting perfectly fine)?

 

All you need to do is take out as much of the crushed coral, this naturally raises ph similar to the effect whole or crushed sea ****’s affect after PH. I would recommend just taking out as much of the coral as you can then do water changes to return the tank to the typical ph of the rainwater.

 

If fish tolerate it well, stability is all you need. Don’t fluctuate your ph too quick or often.

 

All you need to do is take out as much of the crushed coral, this naturally raises ph similar to the effect whole or crushed sea ’s affect after PH. I would recommend just taking out as much of the coral as you can then do water changes to return the tank to the typical ph of the rainwater.

Yah, I knew it raised the pH :/ The problem is going to be getting it out... there's not a lot, but it's around plants and under the driftwood, and filters....

 

If it continues to rise above 8.9 it could lead to problems if it’s stable at 8.6 then that’s right at the maximum thresh hold for good long term living. Stable ph is important most of all but ph outside of the range of 6.0-8/7 can be detrimental for fish in the long term. Outside of that range is considered extreme for the common tropical fish. Not including black water fish or basic water living fish.

 

If it continues to rise above 8.9 it could lead to problems if it’s stable at 8.6 then that’s right at the maximum thresh hold for good long term living. Stable ph is important most of all but ph outside of the range of 6.0-8/7 can be detrimental for fish in the long term. Outside of that range is considered extreme for the common tropical fish. Not including black water fish or basic water living fish.

I think my main concern is that the 8.6 is so high above my normal water. I use a python for this system, and had been doing 50% water changes weekly (mainly so I could trim plants and clean things). Adding that much 7.0 water to an 8.6 "stable" system would be an issue, right?

 

I agree with removing as much CC as possible. I have soft tap water, if I add just a tsp of CC to my 120g, the kh rises to 4.

If your backdrop is alkaline, it is most likely raising the pH as well. Is it possible to mount the backdrop on the outside of the glass? Or possibly paint it in an epoxy lacquer?

 

I think my main concern is that the 8.6 is so high above my normal water. I use a python for this system, and had been doing 50% water changes weekly (mainly so I could trim plants and clean things). Adding that much 7.0 water to an 8.6 "stable" system would be an issue, right?

Yes if you were to do a 50% water change at 8.6 and your new water was say 7.4 that would bring it to around 8.0-8.2. That is an very large difference in hydrogen ion concentration and would cause a lot of stress. I would do daily or every other day 25% water changes to lower the ph after you get as much crushed coral as you can out of the tank to get it back to the normal ph level of the rainwater. I’m just assuming. That it will continue to rise since until remove if it’s a bunch it won’t stop rising for a while similar to the effect of tannins and lowering ph. Their is a stopping point but depending on how much crushed coral you used, you may not be at it yet.

 

I agree with removing as much CC as possible. I have soft tap water, if I add just a tsp of CC to my 120g, the kh rises to 4.

If your backdrop is alkaline, it is most likely raising the pH as well. Is it possible to mount the backdrop on the outside of the glass? Or possibly paint it in an epoxy lacquer?

I can't move the backdrop outside of the aquarium--it's 3D with some large protrusions. I could possibly paint it, but that would require tearing down the entire setup, including removing half a dozen very expensive bucephelandra, anubias, subwasertang and moss patches which are superglued to it...which I don't really want to do :/ Many other people have used concrete backdrops and had them neutralize without further issues, so I think I'm going to try removing other sources which raise the pH first. But thanks for the idea, and I might have to resort to that if this doesn't stabilize/resolve.

 

Yeah, I didn't think concrete would raise the pH but you never know. You must have added a lot of crushed coral....

I didn't know it was so in place either, try to remove the CC and go from there then.

 

Yeah, I didn't think concrete would raise the pH but you never know. You must have added a lot of crushed coral....

I didn't know it was so in place either, try to remove the CC and go from there then.

Concrete has lime in it, which is very basic, and so can raise pH if it's not cure first...which is what I at least tried to do I added about 1/2 a cup of crushed coral at most--it's just a sprinking in some areas of the aquarium, and far less than the amounts in other tanks which I used to raise the pH from 7.0 to 7.6.

Thanks for all the help. Unfortunately I wasn't able to do a water change yesterday--I was completely wiped out when I got home due to some dental work, went to take a nap and woke up this morning in time to go to work :/ No other fish deaths though, so I will tackle everything this afternoon.

 

I reread everything quickly and it seems your pH climbed after you added the CC. I think removing as much as you can is the best deal for now.

But just how soft is your water? My rainwater tests 4ppm TDS, which is extremely low in dissolved solids. I'd have to add minerals to my rainwater if I to use that instead of my 2 degree kh tap water.

 

I would be very surprised if the cc did this. Ive never heard of any amount in a tank being able to get ph higher than 7.8 or so. I would blame the background first.

You could just keep doing water changes frequently to prevent the ph from getting any higher

 

Idk, CC brought it up in my tank when I put it in the filter. I'm pretty sure it can shoot up to 8.3 in a day depending how soft your water, how big your tank is, how powerful your filter is and how much CC you added. Or rise more slowly if it's sprinkled on the substrate.

Personally 1/2 cup seems like a lot of CC to me in a 37g