Will Ph Remain High?

[Mo1959]

Hi all. Still currently cycling my tank. Ammonia levels are always back to zero within 24 hours and nitrite sticking at around 5ppm at the moment. However, just did a ph test and find it is around 8.4 which is a good bit higher than my tap water. Is this caused by cycling and will it drop back a bit once the tank is fully cycled. I am hoping to keep tetras and rasboras and they seem to prefer a lower ph.

Maureen

 

[N0body Of The Goat]

Your tap water could have had a lower pH due to carbon dioxide dissolved in it, which has naturally escaped in your tank..

What you really need to find out is the "gH" and "kH" readings for your tank water, indicating how "hard" your water is. Harder water will resist pH changes, but at the same time, could rule out some species like Cardinal and Neon Tetras (as the hardness is believe to give them kidney failure).

 

[mark4785]

The conversion of ammonia into nitrite and then nitrite into nitrate certainly has an effect on the water PH. I believe the production of ammonia brings down the PH, the production of nitrite highers the PH and production of nitrate lowers the PH (somebody please correct me if I'm wrong).

In addition, tap water does contain more c02 which eventually depletes itself in oxygenated aquariums (usually takes 2-3 days).

You should test your water KH as a higher level will increase your PH.

 

[RadaR]

In addition, tap water does contain more c02 which eventually depletes itself in oxygenated aquariums (usually takes 2-3 days).

The CO2 generally depletes regardless of how oxygenated the tank is.

Bio-acidification. Worth a look.

 

[Mo1959]

Interesting site RadaR. Thanks very much for the link.

 

[OldMan47]

The skeptical aquarist site is a good reference on many subjects. I carry around a link to it in my signature that is marked as Ich info, but my link takes you to the ich page.

 

[Mo1959]

Left some tap water sitting for 24 hours and tested again and it is around 7.2 to 7.4. Hard to read, so either the high ph is caused by the cycle or there is something up with my gravel as that is all I have in the tank at the moment. Got it from Seapets when I ordered the tank so can't imagine it would be that. I asked for the smallest size of gravel so it is actually almost like large grit rather than rounded pebbles. Hope it is OK and not causing the high ph.

 

[OldMan47]

Don't write off the gravel just because it came from a fish shop. My own local fish shops carry African rift lake fish and salt water fish. Both fish appreciate a very high pH so some of the substrates they sell are intended to raise the pH. Try an experiment where you take that tap water and place some in 2 different containers. Add your substrate to one of them and test the pH of both a day or two later. I ended up removing some decorative rocks, about 100 pounds of it in my 125 gallon tank, because I could not control my pH with the rock in the tank and it tested bad using that method. Now my pH in that tank is stable.

 

[Mo1959]

OK OM. Thanks for the advice. Have just removed some of the gravel and added tap water to it along with another container with just water. Will let you know if there is an appreciable difference. The thought of that being the cause and having to completely empty the tank and start over isn't great, especially as I am getting pretty close to being cycled now.

 

[Mo1959]

Oh no!!!! After 48 hours ph in the water with gravel is a good half point higher. My back is dodgy at the moment and the thought of emptying everything and carrying buckets of water and gravel sound horrendous. Is there the slightest chance that whatever the gravel is obviously leaching will lessen over time or will the ph remain high as long as I have it in my water? I really have my heart set on a small community fish set up of mainly rasboras and tetras both of which seem to prefer a lower ph and I want to give them the best chance of a long and healthy life that I can so not sure what to do. Maybe see how the back feels in a couple of days and bite the bullet and empty the whole thing

 

[OldMan47]

Anything is possible in this world but likely is another matter completely. It is not very likely that the impact on your pH will stop. For moving water,why not run a hose out a window to the garden and use that to remove water? Once you have lowered the level enough to make working in the tank easy, remove all the gravel you can and replace it with a non-impacting clean gravel. Refill can again be done with a hose using one of the adapters they make for filling a water bed or a more expensive alternative of the Python system made for aquariums. Leave the buckets for cleaning filters once you are cycled or for acclimating fish in what is called a drip acclimation.

 

[Mo1959]

Hi OldMan. Yes, I have pretty much decided to remove the gravel. It is definitely what is pushing the ph up and I don't think I would ever be happy with it now I have found this out. Have ordered sand today instead as I am quite fancying the idea of corys in the future. They would be nice peaceful companions in a tetra/rasbora tank and I think they all pretty much prefer the same water conditions and temperature. I presume the best thing to do whilst carrying out the replacement is to put my filter in a bucket of the tank water for the couple of hours or so it will take to change things over as my cycle is probably around two thirds done and I don't want to risk the bacteria dying off. I am sure a couple of hours will be fine? I think I may try your idea of running a hose out to the garden. Will be quicker and easier on my old back than carrying around 20 buckets!!

Maureen

 

[OldMan47]

It will be much easier on your back.
If you only expect to be down for a couple of hours, just drop the filter media in a bucket of tank water and go take care of the gravel change. Once it is done, set up the filter on the tank again and recharge the ammonia.

 

[Mo1959]

Well that's it changed over to sand. Got some nice pool filter sand from a seller on ebay. Lovely clean sand. Only needed a couple of rinses and hardly any dust of it at all. Looks nice in the tank. Will have to watch for trapped air though I think. I could see little pockets in the sand just after filling it. Ran my fingers through it the best I could and a lot of air bubbles came up. Even doing this, hardly any dust off the sand so I am impressed. I think I will need to devise something to rake through the sand occasionally.

All that remains to be seen now is whether it sets the cycle back a wee bit. Kept the media in a bucket of the old tank water and redosed ammonia right away so hopefully all will be well.

 

[OldMan47]

That sounds great to me MO. With the pool filter sand you are in good company here on TFF. We have had quite a large number of people switch to sand.