Low Ph 6.0

[cybortech]

Hello,

Just completed testing my water and found PH about 6.0 - 6.2. It has always been constant at 7.0 but the previous months i have seen it dropping and was wondering what causes PH to Drop?

Other stats are

Amm - 0
Nit - 0
Nitrate - 50

Does fish waste have any effect on PH?

I do not have any live plants in my tank as the Tinfoil Barbs eat everything in there way, can this have an effect?

Filled a bucket of tap water left for 24hrs and checked the Ph it was 7.0.
Straight from the tap it was about 7.2.

I know it is quite important to have stable PH but also I'm not to keen on adding any chemicals to increase this unless told by the Enthusiasts on this site.

Some of the fish in my tank do require a higher PH so what would be my next step?

Thank you.

 

[nmonks]

Over time the natural tendency of the water in the aquarium is to become acidic. It's mostly organic materials in the water that do this, some from decaying plant matter and some from uneaten food and fish waste. In much of Scotland the water is naturally soft because it is collected from areas with granite and other insoluble rocks. In England, where the rocks are typically limestone, the water picks up calcium carbonate and becomes much harder. This is, incidentally, why Scotland is better for whiskey (which needs soft water) while England is better for beer (which needs hard water).

Anyway, if you have pH 7.0 out of the tap, you likely have soft water. So there's little to stop the gradual acidification. One solution would be to add a small amount of coral sand to the filter. Put the sand in a small mesh bag (or piece of an old nylon stocking) and as the coral sand dissolves it will buffer the water. This is a bit hit and miss and you will need to experiment a bit to get the right amount. Also, every time you clean the filter you will need to thoroughly was the sand to wash away bacteria that will coat the grains preventing them from dissolving.

The alternative is to simply take advantage of the situation and keep soft water fish. There are many of these, and some will do well down to pH 5 (e.g. many of the Amazonian and Asian "blackwater" species). The danger here is that biological filters do not work well at very acidic pH levels, and also the aquarium become intrinsically unstable. You will need to test the pH at least once a week, or else perform frequent water changes to roll back any unwanted acidification.

Adding a buffering agent is a third option. There are lots on the market. If you had livebearers and brackish water fish, then simply adding sea salt would have done the trick, but with community tropicals you would do best deciding on a pH and buying the appropriate buffer. A pH of 7.0 is very useful and is suitable for most standard tropicals except livebearers.

Cheers,

Neale

 

[cybortech]

Thank you for the reply Neale

I do 25% water changes every week if I done it twice a week would this help to Increase the PH back to normal or would it create other Issues?

Thanks again.

 

[nmonks]

This should be fine. It's a good idea, in fact. The more frequently you do water changes, the better. In most cases, you can't do too many. The trick is to avoid sudden changes in pH. So a 25% change twice a week is likely better than a 50% change once a week.

Since the tanks been steady for a few months and only dropped recently, you might think about what's changed. Does the gravel need a good clean? Are there a lot of dead plants? Stuff like that.

Cheers,

Neale

I do 25% water changes every week if I done it twice a week would this help to Increase the PH back to normal or would it create other Issues?

 

[Kevstir]

way hay a fellow local man

I'm also having the same trouble m8 , its the bog wood in my tank that's causing it , I'm just going through a cycle at the moment so no fish harmed , every time the pH goes below 6 my cycle stalls , im just adding baking soda at the moment to keep the pH up until its cycled, hopefully when i do a huge water change the bog wood will have released most of the tannins so that the tank will become more stable ..

we must have a very low kh in our water , not had a chance to test it yet though..

Kev

 

[Creature Seeker]

way hay a fellow local man

I'm also having the same trouble m8 , its the bog wood in my tank that's causing it , I'm just going through a cycle at the moment so no fish harmed , every time the pH goes below 6 my cycle stalls , im just adding baking soda at the moment to keep the pH up until its cycled, hopefully when i do a huge water change the bog wood will have released most of the tannins so that the tank will become more stable ..

we must have a very low kh in our water , not had a chance to test it yet though..

Kev

That must be why my tank stalled also. My cycle was going well but the ph went below 6 and now getting high ammonia readings.

Think I'll change some of the water tonight!

...

 

[nmonks]

Good call, well done.

Bogwood isn't normally a problem in tanks with hard or brackish water, but it can be difficult in soft water conditions. I'd still be tempted to see where the pH levels off. If it's only 6.0, then coupled with regular water changes, you actually have superb conditions for angelfish, neons, gouramis, rasboras, and so on.

Cheers,

Neale

I'm also having the same trouble m8 , its the bog wood in my tank that's causing it

 

[robyngunston]

Hi there,

I had the same problem, it was what caused my cycling process to stall as well. The lfs recommended what looked like coral rocks, he said to put them near the filter and they should help?

 

[nmonks]

This will help, but only temporarily and not very effectively. Once coral (or tufa rock) is covered in algae and bacteria, the dissolution rate drops to nearly zero. This means very little calcium carbonate is dissolving into the water, which in turn reduces the buffering ability profoundly.

The best solution is to put a quantity of crushed coral or coral sand into a filter, where it can be cleaned and replaced every couple of weeks. Pouring boiling water on crushed coral/sand will clean it pretty well, so what I'd do is have two batches, and alternate between having one in the filter and one being cleaned and ready to use.

Most filters have compartments for chemical media, but if not, you can by filter medium bags from the fish shop.

You'll need to play around with the amount of crushed coral/sand to get the right degree of buffering without taking the pH and hardness too high. You're aiming for about 7-7.2 for most generic tropicals, a bit higher for livebearers and rainbows.

Cheers,

Neale

The lfs recommended what looked like coral rocks, he said to put them near the filter and they should help?

 

[Egmel]

way hay a fellow local man

I'm also having the same trouble m8 , its the bog wood in my tank that's causing it , I'm just going through a cycle at the moment so no fish harmed , every time the pH goes below 6 my cycle stalls , im just adding baking soda at the moment to keep the pH up until its cycled, hopefully when i do a huge water change the bog wood will have released most of the tannins so that the tank will become more stable ..

we must have a very low kh in our water , not had a chance to test it yet though..

Kev

I have very high kh and gh (almost liquid rock) but my tank did exactly the same thing when I was fishless cycling. It's to do with the byproducts of the nitrogen cycle I think. I found the best solution was to do water changes, check the ammonia level and top up if necessary. This also helps keep the nitrite low enough that the bacteria have a chance!