Big P H Drop On Cycle. Help!

[andy_sheff]

im on day 11 of my fishless cycle, topped up with amonia on day 9, tested just now and ph is low. The colour is a weaker yellow than the lowerst on the api chart. Nitrite is off chart and nitrate is between 40 and 80, prob more around 80. What should i do? Its not good having ph low is it? Its about 7.6 out of the tap.

 

[OldMan47]

Try a large water change. The form that nitrites and nitrates take is often an acid which will drive the pH down. All it takes to bring it back up, in many cases, is a large water change to remove some of the nitrates. If that doesn't fix it right away, come back and there are other things that you could do. A water change is always the first choice for water problems. Don't forget the dechlorinator.

 

[andy_sheff]

right, i thought as much! Ile do an 80 percent change.Does temperature matter much?

 

[OldMan47]

Not at all for a fishless cycle. Once you have have fish in the tank you will want a rough temperature match with the tank temperature. It is always better to err on the side of low temperature rather than too high. As water temperature increases, the amount of oxygen the water can hold goes down.

 

[andy_sheff]

done it. Done big water change. Topped up with amonia and de chlor stuff. This sand might have been a bad idea. Nightmare cleaning it.

 

[fatheadminnow]

To clean the sand, you just hover the siphon about 1 cm above the sand and swirl the end of it in circles. That will allow the fish waste and debris to get sucked up and not the sand.

Try to aim around 84F/29C for temperature, as that is optimal for the growth of the bacteria in your filter.

-FHM

 

[andy_sheff]

done it. Done big water change. Topped up with amonia and de chlor stuff. This sand might have been a bad idea. Nightmare cleaning it.

 

[waterdrop]

When you're fishless cycling, or in general have an aquarium, I always think its quite helpful to have a simple spiral bound notebook and form the habit of making daily entries. In your case this will help you be able to look back and see how many days it now takes for pH to drop again.

A fishless cycle stalls out at about pH=6.2 and is definately at a complete stop at pH=6.0. The ideal pH for most rapid bacteria growth is 8.0 to 8.4 but its usually not worth artificially raising pH unless you are having severe problems with it stalling out.

~~waterdrop~~

 

[andy_sheff]

ive raised the temp back to mid 80s, ive been checking the amonia every 12 hours or sometimes 24, im gonna start checking the other things every day now after this, i suppose nitrate and nitrite doesnt matter at this point? i did that to clean the sand, worked well but when your messing about in tank, debris seems to come aback straight bazaw!

 

[waterdrop]

Yes, totally normal, aquarists I know rarely bother to judge the water clarity after they've messed in the tank until the next day, takes quite a while to settle all back down.

~~waterdrop~~

 

[andy_sheff]

my ph has dropped again! Just checked. Tap is 7.4 or more. The tank is 6 or less, similar colour to 6 but weaker looking, what shall i do. What is happenin!

 

[andy_sheff]

my ph has dropped again! Just checked. Tap is 7.4 or more. The tank is 6 or less, similar colour to 6 but weaker looking, what shall i do. What is happenin!

 

[waterdrop]

The -process- is normal but the result requires action on your part.

Once you have some N-Bacs and they start converting some of the nitrite(NO2) into nitrate(NO3) you will start to get acids in the tank (NO3 reaches an equilibrium with some of it being acid, nitric acid I believe) and the H+ ions (or equiv) floating around will either find negative ions from the minerals in your water or they will still float around and will drive your pH downward sharply. In your case they are not finding enough negative ions from minerals, so your pH is going down.

The first action to take is to plan and do a large 90% water change (with your gravel cleaner siphon, you've got one, right?) and be sure to use dechlor (conditioner) to treat the return water (in fact 1.5x the recommended amount would be good at these early stages of your fishless cycle).. you can either temp match or let your heater bring the temp back up, doesn't matter much to the bacteria as long as it eventually gets back up to the 84F/29C you've been keeping. Also don't forget to recharge your ammonia.

Your tap water should have more minerals and you can measure pH an hour or so after the water change. Then let's see how long this pH lasts before the members decide on whether there should be more drastic actions.

~~waterdrop~~

 

[andy_sheff]

thanks waterdrop, yes i have a syphon cleaner thing, sand is my substrate so i just suck the surface debris off. ile do the process again when i get home at tea time and post up when its done for refrance. seems rather quick that it has dropped again.

 

[waterdrop]

The "more drastic action" is to add baking soda (not baking powder because its more unpredictable in extra ingredients in my opinion) at a dosing of about a tablespoon per 50 liters in order to raise your KH, providing more buffer for the acid. But its better to try just a water change once or twice first just to see if that alone will buffer you enough to get through your fishless cycle. After a fishless cycle is over, there is less overall push in the acid direction usually.

~~waterdrop~~