Ph dropping...

[WTM]

I have a small tank (approx 40lt) that has been running now since June, it has been cycled, plants and an appropriate number of fish added (1 Betta, 3 Bronze Cory, 1 Platy).

Doing a test in the weekend before carrying out a water change, I noticed that although Amonia and Nitrite were at 0ppm, with Nitrates at 10ppm, the Ph had fallen to about 6.4. The Ph during/after cycling had settled at a stable 7.0. I then carried out the usual weekly 8lt via a gravel vac.

I retested yesterday and the tank ph was at 6.5 (Tested tap water at 7.2) -> a further 4lt change.

Today still at 6.5 -> 7lt change undertaken.

Am at a loss to what is causing the sudden Ph drop, does anyone have any suggestions?

Perhaps I am overfeeding?

[Pegasus]

Hi WTM... Welcome to the NZ Fishroom

I think if the cause was overfeeding it would show up in your readings.

Just a few questions...

Has it just started doing this recently..?

If so.. what has changed,,?

Are you using fertilizers... CO2 or anything..?

Have you any logs or driftwood in the tank..?

Both the above will cause a pH drop.

You can stabilize your pH by adding some Oyster or Shell Grit to your filter.

Put a handful in a nylon stocking bag (Ladies tights).. and pop it in your filter. This will raise the pH "gradually".. so you need to keep checking and replace the grit around every week or ten days.

HTH

[WTM]

Just a few questions...

Has it just started doing this recently..?

If so.. what has changed,,?

Are you using fertilizers... CO2 or anything..?

Have you any logs or driftwood in the tank..?

Hmm it's happened in the last two weeks.

I use Flourish plant supplement (weekly 3/4ml dose) and Flourish Excel (normally, but not in the last week)

No logs or driftwood.

I have had somewhat of a snail problem during this period (a huge population explosion, and hence their by products).

Thanks for the advice...

[Caryl]

There you go then - acidic snail poo!

[caserole]

Hello WTM,

It would be nice to know your real name - more friendly

ok this is probly what your problem is as I am from upper hutt too.

there is bugger all ph buffer in our water , so when you get just the slitest amount of nitrate in your tank ( nitrate = acid ) it will cause your ph to drop from 7 to well that depends on the level of nitrate it could get really BAD if you don't keep up thou's water changes .

there is 2 ways to fix

1, do a 5% water change 5 to 6 days a week = 30% over the week

2, add buffer to your water . this is what I do, I do 1 as well :lol:

how to add buffer to your water

1, find a small piece of dolmite rock ( if you can find some, tell me I want some )

it works like this the acid in you tank desolves the lime until the ph hits 7 then it is nutralised ( or close to it )

2, add half a teaspoon of sodium bicarbonate ( = baking soda ) per 100lt , you must add a % of bicarbonate every time you do a water change to keep your ph balanced

adding this amount will give you a final ph of around 7.2 to 7.4.

if you use method 2 DON'T add all the b/soda at once just add a % every water change and in 2 to 3 weeks at a 30% water change per week your tank will be fully buffered .

any other ideas people? more the marryer

[klaymann]

the tank might be loaded with too much plant .. ph drop over night ?

[caserole]

Just had a thought , it may be wise to do a test of ph and nitrate on your tank .

What I mean is this:-

test your waters ph everyday first in the morning early then again in the evening , this will tell you if there is a flucuation during the day/ night - and threw the week and again before you do a water change and after you do a water change ( record results for referance )

the perpose of this is to see what is happening to your tanks ph and it would also help figger out what is the cause, a nitrate test once per day would also help ( upper hutt has low buffer nitrate = acid = lower ph ) .

this way you would be able to track your ph and compare it to you nitrate level to see if there is a corolation (is nitrates the problem of lowering ph )or if there is another cause .

just an idea that may have an easy fix

oh by the way 0ppm nitrate is best but 10ppm nitrate is nothing to worry about.

[WTM]

Thanks for the advice guys... I had considered the snail poo issue (there was a stupidly large number of them suddenly appear (spent 2-3 hours in one go removing them the other week).

Tomorrow is water change day, so will test before, after and then each night and morning to see what happens over the week.. (noting any water changes).

In regards to water changes, I do a 20% change weekly...

Also I will start testing Scooter's (turt) tank to see what's happening there... might help exclude some issues (has no plants in the tank)

WTM

[caserole]

A 20% water change per week is just fine

keep an eye on those nitrates if they start to climb you may like to increase the water changes to half weekly as the tank is only a small 1.

DON'T FORGET TO LET US KNOW YOUR RESULTS

[WTM]

I have thought of increasing it to to 30%, but was worried that might be too big a change?

The Nitrites and Ammonia are nicely behaving themselves at 0ppm, but what is a "normal" or "okay" level for Nitrates to rise to over the week between water changes?

W

[WTM]

Okay, did a 30% change yesterday, and PH climbed back to 6.6 when tested later in the evening.

Interestingly I tested the turtle tank, and the ph for that was about 7.2 even before a waterchange. Would seem to suggest it's not lack of buffering causing the issue..

Perhaps it is too many plants?

Thoughts people?

[caserole]

Yes it would appear so but doesn't mean it is so.

then you say "to many plants" what do you really mean?

if you have alot of plants that are growing well.

your ph during the day will be normal.

but at night the plants breath O2 in and CO2 out ( CO2 is acidic ) just like your fish.

this can cause a crash in you ph and a crash in your O2 level over night that is not good at all, but will recover during the day.

this is why I suggested you take readings of your ph in the morning and night.

the morning reading if your plants are at folt will be lower then the night reading and this will persist day after day - you will see the patern.

hope this helps

sorry i've been off line for a few days

*what is normal or ok for biocem's? *

ammonia 0ppm,

nitrite 0ppm,

nitrate now this is a little differant if your tank is in balance the norm is 0ppm,

but if your tank is no higher then 20ppm the fish want be unhappy,

the problem comes if you get flucuations up down up down or you add new fish that are used to very low or no nitrates.

it can be a bit dorenting "nitrate levels" but as I suggested if you test your nitrate level dayly you will see what is happening in your tank and tell us - we can go from there and see what others have to say

[Caper]

Tested tap water at 7.2

WTM...how doyou test you tap water. Long ago I found a site that said how to do it...and I forget...don't you have to let the water sit for awhile before testing????

Thanks

[WTM]

WTM...how doyou test you tap water. Long ago I found a site that said how to do it...and I forget...don't you have to let the water sit for awhile before testing????

Thanks

I actually just tested straight tap water - doh :lol:

I've tested the tank for most of the week since the water change on Sunday.

After the water change the PH rose back up to only 6.6 and the Nitrate fell to about 5.0ppm

Since then the PH has fallen slightly while the Nitrate slightly raised, with no sudden changes during the night or day, it was just a slow steady change. :-?

Anyway, I've done a 2 gal change tonight, and I intend to another change on Sun, with the intention to continue at that rate until the Nitrate is back down to as close to 0 as is possible. After which I will go back to weekly changes, but will increase to 3 gal.

Unless anyone thinks I should do otherwise?

Thanks

W.