Dropping Ph

[pilsburypie]

Hi all - just joined looking for some advice on a big problem I have with my tank PH. I shall explain as in depth as I can to give you as full a picture as possible. I now have a good PH meter. My PH just wants to drop.

Tank: 170l (probably more like 150l water)
Established: 5 years
Fish: Large (all 7-10cm) - 3 Parrots, 1 Angel, 1 Sevrum, 2 Gouramis, 1 Plec, 1 albino frog (all 1-5 years old)
Fish added: None in the last 12 months
Ammonia, Nitrite, Nitrate: No problem
Filtration: It is a jewel rio170 tank has standard internal filtration
PH: was 3.6 (now up to 6.5 due to regualr water changes and "PH up" additive)
Water changes: was every few months (now twice weekly 25% will drop to once every 2 weeks once stable)

Noticed fish were looking ill - slow, quiet, tatty fins, flicking themselves, thin, white mucus like blotches

OK - as you can see my PH was unbelievably low, I'm amazed the fish weren't all dead. I found out about the problem 7 days ago and have since brought the water up steadily to 6.5 by changing the water (first change 50% plus one later 25% change) and adding "PH up" which is a potassium hydroxide 9% solution. The fish are all looking much better and far less stressed.

My problem is that the PH wants to drop like a stone. I monitor it daily now and it damn near drops 1PH/day. The only halt to it is me adding a load of the "PH up" daily and changing another 25% water every few days.

I have been told that the water in my area is a problem (forgot if he said hard or soft but you may be able to assume which it is!) and it would be necessary to 25% change every 2-4 weeks to maintain, but my tank would be back to 3.6 by then.

I am aware of my previous mistakes like very irregular water changes due to my ignorance, but this is no problem now as I am aware of the need. The PH must have been low for ages, but likely dropped to it's all time low fairly quickly as the fish were always fine until this recent episode.

Is this rapid drop due to the tank still being in recovery or is there another reason......

Advice would be really appreciated - sorry for my long winded rant!!

Mark

 

[Miss Wiggle]

3.6!! thats crazy

keep monitoring the ammonia and nitrite as you bring the pH back up. The nitrifying bacteria that usually keeps these levels in check can't live in a pH under 5, however there is another sort of bacteria that will develop that can do the job. However you may find as the pH comes up these bacteria will die off and new will have to grow, so your tank may go into cycle. Don't panic cos this may not happen at all, as the tank is well mature it may be able to cope with it, just something to watch out for though.

what's the pH of your tap water, can you also give full details of what decor you have in the tank, what substrate etc as various things can affect your pH.

It is normal for the pH of a mature tank to fall, however I don't think it should go that low

 

[pilsburypie]

3.6!! thats crazy

keep monitoring the ammonia and nitrite as you bring the pH back up. The nitrifying bacteria that usually keeps these levels in check can't live in a pH under 5, however there is another sort of bacteria that will develop that can do the job. However you may find as the pH comes up these bacteria will die off and new will have to grow, so your tank may go into cycle. Don't panic cos this may not happen at all, as the tank is well mature it may be able to cope with it, just something to watch out for though.

what's the pH of your tap water, can you also give full details of what decor you have in the tank, what substrate etc as various things can affect your pH.

It is normal for the pH of a mature tank to fall, however I don't think it should go that low

Thanks for your quick reply. 3.6 is mad eegh? The bloke in the fish shop I go to said at 5 they may start to die!

I shall monitor the ammonia and nitrite as you said.

Here is the answers to your questions: PH of my tap water is 6.6. The decor is as follows and has all been in situ for the whole 5 years. The substrate is just aquarium pea gravel type of stuff. I have a couple of rocks, one is a metamorphic quartzite, one is a piece of amethyst crystal and the other is a piece of shale. I have a large piece of bogwood and a couple of sea shells. There are also numerous plants, all purchased from the fish shop (I don't know their names). All established.

Mark

 

[Miss Wiggle]

well although i think it's unlikely that the decor is causing any problems especially after all this time you just never know, so i would take out all the bogwood, rocks etc etc and give it a few days see what happens.

leave the plants so the fish still have some cover, it's pretty safe to say they won't be causing problems with pH.

now although a pH that low is very dangerous, adjusting the pH too quickly could also cause problems, your fish haven't died so to some extent they are acclimitised to the lower pH. make any changes very slowly and carefully.

what filter media do you have and when was it last changed?

 

[thegnu]

you have probably got practically no KH or GH. the KH acts as a buffer to help keep your water stable so you need to raise it. i would put baking soda into 20L of water,( but only a tiny amount, half a teaspoon is even too much) give it a good stir and add limestone, coral sand, leave it for 3/4 days and check the pH KH. you are looking for a pH of about 6.5 and a KH around 5/6 add the water to your tank. keep doing this so you don't change your water too quickly. you might put some ro right in later to help with the GH, or if you have plants add a liquid fert for the metals/minerals, but make sure you take dead or dying leaves off, give your gravel a good and regular vac and keep up with water changes. it wont hurt to make sure you have enough filtration/aeration as well

 

[MHunt]

Yeah i was going to say, water hardness acts as a buffer to stop the pH crashing like that. check what is coming out of the tap, if that has changed, perhaps your water supplier has changed something recently.

 

[seanyt66]

Hi

I have just had a very similar problem, i spoke to my LFS about it and they said ( as has been stated above ) that it was linked to my KH. They suggested Nutrafin PH stabiliser which raises the KH and pulls the PH up with it - you dose a little a day and bring it back slowly.

It worked a treat in my tank, you should give it a try

Regards


Sean

 

[pilsburypie]

you have probably got practically no KH or GH.

Excuse my ignorance, what is KH or GH?

Thanks everyone for the replies

Mark

 

[thegnu]

KH is Carbonate hardness or temporary hardness, GH is General hardness

 

[thegnu]

http/www.drhelm.com/aquarium/chemistry.html

 

[Arimus]

you have probably got practically no KH or GH.

Excuse my ignorance, what is KH or GH?

Thanks everyone for the replies

Mark

In a nutshell: GH is (as stated) a general hardness measure, KH is the carbonate hardness. The higher the KH value the more 'stable' the ph value of your water will be.

 

[pilsburypie]

http/www.drhelm.com/aquarium/chemistry.html

Fantastic - I shall get on the case right away

Mark