Re: PH Swing - Help

[Lex2000]

Hello Folks,:(:(:(:(:o

i'm new to discus keeping. I been ok for the past 4 week till this week my PH dropped to 4.0.
I did nothing to change the tank. It’s bare bottom tank with hydrosponge and Hob filter, 20g, feeding 3 times, tap water Ph 6.8-7

Please help.

[ed8t]

Sounds like you have very low KH. Whereabouts do you live? How much water changes do you do? Frequency? Are you checking your pH with a meter?

A heavy bioload ie. a few discus in a 20 gallon tank could cause the pH to slide real fast if you have low KH readings. Our water in Vancouver is very soft, TDS 0 ppm, barely readable KH levels, pH out of the tap is about 7.0. I buffer all my tanks with crushed coral w/aragonite, pH rises to 7.6 if I use a fair bit of the buffering material, but it never moves from there. Daily water changes help maintain the pH too.

[dpt8]

Great advise,,I too had to buffer my tanks ith chunks of argonitecoral in the tanks..Keeps the ph from crashing.. Could use a little Arm and Hammer to gradually raise the ph. The argonite is the brownish crunk in the left of this pic.. :9)

[Graham]

Hello Folks,:(:(:(:(:o

i'm new to discus keeping. I been ok for the past 4 week till this week my PH dropped to 4.0.
I did nothing to change the tank. It’s bare bottom tank with hydrosponge and Hob filter, 20g, feeding 3 times, tap water Ph 6.8-7

Please help.

That is called a pH Crash and it occurs when all the KH is used up, which buffers against the acids prodcued in the tank.

Start doing water chnages to get it back up into the 7.0 range. The you can use a buffer to hold it there or do very regular water changes, testing the KH as you go.

You'll probably have a bigger problem now in that the crash would have wiped out a large percentage of the nitrifiers...check NH3 and NO2....use binders, water chnages and salt to protect the fish...the tank will probably re-cyce itself

[Lex2000]

I'm in Vancouver (South Van)
Tap is at PH 6.8 - 7
20G tank w/ 2 4" discus.
I'm using a Oakton Tester 20 Ph tester

I been doing 2 - 3 water changes /w prime.

I left 3 sea shells in the tank this morning with the sharp edges facing down.

I did put a sag of argonite last night still it didn't go up.

[ed8t]

If you've only done 2 or 3 waterchanges since you owned them, I'd do a minimum 50% daily from this point onwards. As Graham said, your bio filters may be toast, so you'll have to watch for ammonia and nitrite levels.

I age my water the night before a water change with a corner filter filled with crushed coral and aragonite. How much aragonite are you using - is that in your hob filter?

[Lex2000]

2 - 50% water changes daily on weekdays.
3 - 50% water change daily on weekends.

my sponge is cycled, i have handful of argonite in a pantyhose and sitting beside the sponge.
HOB has regular sponge (1month old).

[Graham]

Lex While shells and crushed coral etc will raise the KH, they generally can't respond very fast. If your water has a really low KH to start with then it's possible that the KH could go to 0.0ppm during the night, allowing the pH to crash.

The KH is bicarbonate or carbonate depending on pH of the water and in most freshwater cases, it's bicarbonate. That bicarbonate is a source of carbon for plants and the bacteria. The plants give it back during the day but the bacteria don't.

This can really be seen in heavily planted tanks by checking the pH in the early morning before the lights come on and at night after the lights go out. There will be a natural swing in pH.

This is why KH slowly drops over time. This is also why it's called temporary hardness as compared to GH which is permanent hardness, The natural processes in the tank are using it up......buffering chemistry:bandana:

The quickest source for KH is baking soda, sodium bicarbonate, it has a natural pH of 8.4. So a little can go a long way.

So with out a good source of KH the pH can crash out easily at night.

Hope this helps answer your question in the PM

Graham

[Lex2000]

i added a tspn of baking soda lastnight and the PH seems to be stabilized at 7.1.

i wonder how long i have to do this till i can go w/just the tap water.

[Graham]

Whats the KH of the tap water....

[Lex2000]

KH, 10-20ppm

[Graham]

That is really low and basically offers no buffering ability. 30 > 40ppm should be the absolute lowest.

[Lex2000]

so, should i just maintain KH by adding Baking soda?

[Graham]

Try with the aragonite or crushed coral but you may find testing and using the baking soda the easiest at the moment.

Adding small amounts bring the KH up to 40ppm...the pH will come up a bit as you're doing it.

G

[judy]

but do it slowly... over a period of hours with each little incremental change...

[Lex2000]

Thanks guys.. i will do that.

I already have a 200g of crushed coral in a stocking liner, i added 1tspn of baking soda. I did 3 - 50% WC yesterday, left this morning with another WC, 1tspn of baking soda, 4tablespoon of Aquarium salt, and their food.

PH was at 7.1
KH 10-20ppm
TDS 130PPM

[ed8t]

Is there any way your sack of aragonite/crushed coral inside your filter? I add a cup of that inside my Aquaclear hob and that maintains a steady pH for me.

[Lex2000]

i have small ehiem elite hob and no 5. hydrosponge
i can put small amount in there.

[kaceyo]

My KH from the tap is 2dKH. With daily wc's (one) even my slightly overstocked tanks stay well within acceptable limits for pH. It never drops below 6.5 within 24hrs of a wc and is around 7.0 right after. I'd think 10 to 20dKH would be fine.

Kacey

[Lex2000]

I want to thank all of you for helping me out during this disaster.

my ph is back up to 7.1

i know it's bit high, i will take the coral out for few days.

[ed8t]

pH of 7.1 isn't high, if it's stable I'd leave it.

I leave my crushed coral/aragonite in the filters all the time for my juvenile fish. Stable pH @ 7.6, another source of calcium for our mineral poor water, fish are growing and happy. I supplement our water with additional calcium chloride and epsom salts for grow outs.

[April]

Lex..rinse your sponge..and you gotta get a bigger tank. 20 gallons is getting too small for them. easier to maintain in a bigger tank. thats the trouble with our vancouver water. its almost like ro water. once it starts sliding..it will keep on sliding .
well glad you have it under control..but i think if you had a bit bigger tank the water would stay better. if the filter wont keep up or lots of stuff in it..it will slide fast. i try to keep two filters going and alternate rinsing. of course if you lost your bio you dont want to rinse it too much right now. but as long as its not full of brown munge. try find a 33 gallon tank they would do better. i know even if i have a pair in a 30 gallon here i find it hard keeping the water good enough to get good hatch of eggs and happy parents. they get stressed easy .