Ph shifting

[plankton]

If the ph has dropped that low it means all the carbonates have been used by the munchers during the cycle.
There are three ways to sort this...
Water change - this won't cause any problems.
Adding sodium bicarbonate (dissolved before adding to tank, about a teaspoonful) - this can cause problems long-term as it leaves behind sodium compounds which are used by anything.
Adding potassium bicarbonate (as above) - this will leave potassium compounds which will get used by plants.

[Martinspuddle]

Attention ladies: @black ghost, @Stephen & @plankton.

Whole reason I 'no' to the third question was @Clem Fandango has added 9 kgs of Tropica Aquarium Soil to this aquarium. This soil substrate does effect the PH, KH and GH and from my experience of using this product, I would suggest this is giving lower test results. You could say it's causing false readings compared to the tap supply.

Tropica say:

Aquarium Soil is further an active bottom layer that lowers the pH value and slightly affects the water chemistry

Given the OP has in the 90 litre aquarium, 9 kgs of Tropica Aquarium Soil, so the affects will be much higher than stated.

(Tropica aqua soil (9kg in a 90L tank - capped with at least an inch of sand/fine gravel)

I put twice that amount of Tropica soil in this aquarium and my test results hit the floor for the first few months and you all know what the tap water is like in North Kent.

Link: Tropica Aquarium Soil

[black ghost]

Attention ladies: @black ghost, @Stephen & @plankton.

Why thank you kind sir.

Not sure what you’re getting at here though. The pH is 6 (because of the soil). That means the answer to the 3rd question is yes. The pH needs to be raised for the cycle. The wee critters’ll work down there but they won’t hardly multiply.

[Martinspuddle]

Attention ladies: @black ghost, @Stephen & @plankton.

Why thank you kind sir.

Not sure what you’re getting at here though. The pH is 6 (because of the soil). That means the answer to the 3rd question is yes. The pH needs to be raised for the cycle. The wee critters’ll work down there but they won’t hardly multiply.

Because Tropica Aqua Soil you will get a lower test results than you would using a inert substrate. I found it made little or no difference to the cycle time of a aquarium with this soil.

There have been mentions of adjusting the water hardness which is pointless with the soil used.

[black ghost]

Yeah it’s just a general ‘rule’ that nitrification slows and stops at 6, 6.5 or whatever, but some bacteria can nitrify at 3.5, and our tanks don’t all grow the same species. Then there’s archaea, which will grow instead/also if the ammonia and/or nitrite are very low. And I’ll guess there could be bacteria on the soil...

[Clem Fandango]

There have been mentions of adjusting the water hardness which is pointless with the soil used.

Should the chemistry change over time based on the release of botanicals from the soil? My other planted tank gives a 7.8 PH reading which is the same as my non-planted. I believe the capping layer in those have coral sand in them. I am thinking adding a bag of coral sand to my filter could possibly be my solution to water readings showing ammonia and nitrite levels going up and down while nitrate reads no higher than 5.0.

Scratching my head but the input from everyone is definitely really helpful, so thanks all

[Martinspuddle]

I found it made little or no difference to the cycle time of a aquarium with this soil.

Concerned about nitrification process slowing with a lower PH, so I removed a sample of aquarium water in a jar and I let it stand over night. Morning, testing showed a PH of 7.

Remembering I always cycle naturally (no Ammonia added) the cycle time was longer than normal but not by much.

[Martinspuddle]

There have been mentions of adjusting the water hardness which is pointless with the soil used.

Should the chemistry change over time based on the release of botanicals from the soil? My other planted tank gives a 7.8 PH reading which is the same as my non-planted. I believe the capping layer in those have coral sand in them. I am thinking adding a bag of coral sand to my filter could possibly be my solution to water readings showing ammonia and nitrite levels going up and down while nitrate reads no higher than 5.0.

Scratching my head but the input from everyone is definitely really helpful, so thanks all

I wouldn't, and yes, your nitrification process will be longer. I followed Tropica instructions of weekly 50% waterchanges and once cycled you'll find the PH in your aquarium will stabilize.

[black ghost]

ammonia and nitrite levels going up and down while nitrate reads no higher than 5.0.

If ammonia and nitrite are going up and down then they’re becoming nitrate, so you must be getting false nitrate readings.

[black ghost]

Concerned about nitrification process slowing with a lower PH, so I removed a sample of aquarium water in a jar and I let it stand over night. Morning, testing showed a PH of 7.

Acid that evaporated? CO2? I kinda thought that was what you meant, that’s it’s not a “true” pH drop, but a reading of 6 still means 6....?