ph mystery

[illumnae]

I recently just set up an apisto tank (new to the hobby) and was surprised when i found that my water ph was a very low 4.5...this tank was previously bare bottom and ph was measured to be between 6.0 to 6.5

i had attributed this low ph to blackwater extract, and this was also suggested by a bro in another thread...he said that singapore water is extremely soft and thus blackwater would lower the ph by alot.

i did a test last night, though, and found that my tapwater is ph 7.2 and using blackwater only reduced it to about 6.8....i left the water with blackwater overnight and in the morning it was still at 6.8, so it couldn't be the blackwater that reduced the ph.

in my tank, i have a very thin layer of biogravel, a piece of bogwood with 3 anubias nana tied onto it, a piece of lava rock with taiwan moss tied to it and an apisto ceramic breeding cave. the biogravel was taken matured from a planted tank i had.

filtration for this tank consists of a diy stackable overhead filter with 3 tiers. the top tier contains lava rocks, middle tier has a coarse sponge and ceramic biorings and bottom layer has a fine sponge and activated carbon. the fine sponge contains dust and mulm stirred up when i brought the biogravel up from the planted tank to this one.

at first i thought that it was a freak occurrance that i had 4.5 ph, but after doing a 20% water change with ph 6.8 water, the ph rose to 5.0 but dropped back to 4.5 within 30min. i then thought it was the bogwood, but my friend bought the exact same type of wood from the same shop as me, but his ph is not lowered at all by it (bogwood also doesn't seem to be the type that releases tannins and acids into the water)...my water is also crystal clear with no trace of brown or yellow.

my theory now is that the activated carbon in the filter bound the chemicals in tap water that made the water more alkaline, thus dropping the ph to a very acidic 4.5 (which my apistos, pencilfish and ancistrus seem to love)...or it could be the mulm in the fine filter sponge (but then wouldn't the water be stained if it is?)

i would very much like to solve this mystery so that i know what's making my ph so low and i can maintain it to prevent a sudden accidental spike in ph killing of my fish...can anyone help?

[Shadow]

what substrate did you use?

[illumnae]

as mentioned above, it's biogravel =)

[illumnae]

noone has any idea? =( i'm really afraid of a sudden ph spike when i maintain my filter...trying to refrain from changing the fine sponge even though it's filled with dirt/mulm in case that's what's causing the low ph

my apistos are really happy now with low ph...but i think a spike will kill them =(

[Quixotic]

What are you measuring your pH with? Hmm... is your measuring device reliable?

Try measuring your pH once in the morning, afternoon and night. If your water is not buffered, pH will swing and fluctuate.

[illumnae]

i'm using a ph test kit from azoo...ph hasn't been fluctuating when i test my tank water...it's constantly at 4.5 and my tap water is constantly at 7.2 and blackwater added tapwater (with antichlorine added) is constantly 6.8 =)

[Quixotic]

See if you can get a pH pen to test. Borrow from someone?

I never fully trust pH test kits, as their error of margin can sometimes be too much.

[illumnae]

ok i'll try to borrow a ph pen =)

but it's abit weird still, given i have consistent results from my tank and tap from the kit =)

there's nothing in my tank/filter that's capable of dropping the ph so much right?

[Quixotic]

Could be your biogravel. ADA soil for example will lower the pH, so your biogravel may be in question.

However, before ringing any alarm bells, see if you can confirm the pH via a more reliable method.

[illumnae]

hmm just asked around noone i know has one...all using ph kits lol =) called up polyart too but the cost is quite high, almost 2 blue notes...guess i'll wait around for a 2nd hand one to pop up

will be conducting tests using my kit on my mulm filled sponge (about time to change it anyway) to see if that's the cause...that's my main concern because i don't want changing filter media to spike my ph =)

[illumnae]

well i don't think it's the sponge cuz i just soaked the sponge in a pail of 6.8 water and the ph still hasn't gone down after almost an hour =) it can't be the carbon that's binding chemicals which bring up ph right?

[leeruisheng]

No expert here, but I think your pH is low enough to induce spawning. I managed to breed all my apistos around pH 5. As for water change, I prepare a pail of water with peat in it for over a week long, so that the pH is quite similiar to the tank. So no worries about different pH.

[illumnae]

hi, here's an update:

been monitoring my tank's ph for a few days...ph remains low still, but i notice it isn't exactly 4.5 anymore, has been constantly hovering between 4.5 and 5.0 now...could be because of the 20% water change i mentioned in my first post, but throughout the day it's a regular 4.5-5.0

however, i notice that when i leave the ph measured 5ml water for about 24 hours, it turned into ph 6.0 water...as in the colour changed from reddish orange (red is 4.5 and orange is 5.0...it's in between) to light green (6.0)...is that a normal occurance or does that mean my water fluctuates ph? the tank water still remains low below 5.0 as mentioned

is there a way i can keep my water at a constant 4.5 even after water changes...such as using peat granules? or will the peat granules crash my ph even lower to like 2 or 3 because of the low starting ph?

really need help and advice here!

[illumnae]

thanks for the advice leeruisheng =)

i think if i can't solve the mystery of my low ph soon, i'll have to do the preparation of water beforehand with peat...i'm trying to avoid that due to lack of space and number of pails available to me...usually i drain 20% water out then pour it away and use the same pail again to fill and put into tank

the ideal situation for me would be peat stabalizing my ph at 4.5 or 5 and not crashing it to 2 or 3 if i put it in my filter...that way i can just change water and not worry about the ph as the peat in the filter would keep it low...but that's just wishful thinking right? =)

but my apistos are very happy currently in the low ph water...they're just too young to breed i think...4 months old currently and about 1.5 inches long...just hoping for my ph to be stable and them to grow abit more =)

[Milk]

your tank's ph is ideal to breed Apistogramma ready...If you are worried with the changes in ph,you might want to adopt ruisheng's method of aging water...Age water with peat inside...Add the water in after 1 or 2 days...For me,all my tanks are with ADA soil and there's peat inside each breeding tank(I do not remove the peat at all..remove only to change them..)And i change water immediately without aging..only add anti-chlorine..

Regards
Milk

[leeruisheng]

I think it's because of your blackwater extract. Do you add them?

[illumnae]

leeruisheng: i add blackwater extract, but i also did a test with it....water from my tap is about 7.2 after blackwater added it is 6.8... i then age the blackwater for 1 day and the ph is still 6.8, so i don't think it's the blackwater that causes the ph to drop so low

milk: so with my situation is it safe for me to just add a bag of peat granules into my filter and it won't crash my ph too low?

[Milk]

Btw,what the substrate that you are using for that tank??

Regards
Milk
Ps: Valice/vincent...I think you should split this into another thread..

[illumnae]

using biogravel for my tank, some german brand one not too sure what it is but not ocean free =)

[leeruisheng]

Get a test kit and dose slowly. It takes quite some time for peat to lower pH. But maybe if you want to induce spawning, can try blackwater extract from Tetra. It doesn't really lower pH. To me it doesn't cause after dosage did a pH check. There's no change. If it works then no need to lower pH. Save the trouble.
And for your info, if you were to add peat, it will brown your water. A little bit of blackwater doesn't change the colour much.