alkalinity consumpution in new tank

[johnj]

my tank is 24 days into cycle using doc tims one and only and ammonia " Still got nitrite at around 0.3-0.6 and 25 nitrate"

but wy does my tank consume alkalinity with no coral/fish ? it went down as low as 5.6 dkh so added 143ml 10 days ago to bump upto 7.3 dkh " I added another 44ml of red sea foundations B alkalinity last night whot calculator said would get me upto 8.2 dkh" After checking 30 minutes after dosing" it only went up to 7.6 dkh
But did 2 Hannah checks today and alkalinity has gone down to 6.9 dkh ?

whots going on with tank!

 

[W1ngz]

Coraline algae will consume elements from the water. Unusual in such a new tank, but not impossible,especially if you have the lights on.
Are there green or purple spots starting to grow on the glass or rocks?

 

[johnj]

Coraline algae will consume elements from the water. Unusual in such a new tank, but not impossible,especially if you have the lights on.
Are there green or purple spots starting to grow on the glass or rocks?

I only put lights on for say 4 hours day and got no green or purple spots around tank or on glass"

iv added 45kilo of reel reef rock that had bean soaking and maturing for months in shop if that would take up alkalinity

 

[SeaDweller]

What test kit are you using and did you recheck it?

 

[johnj]

What test kit are you using and did you recheck it?

I used a Hannah checker and a salifert" 6.9 Hannah and 7.3 salifert

 

[W1ngz]

There may be some precipitation going on somewhere. I doubt it's from the rock.

There is a fairly wide margin to work with between them, but there is a link between all three major parameters and solely focusing on one while ignoring the other two could also be a problem. What are your calcium and magnesium levels at?

Alkalinity is unimportant to an initial cycle. Your best bet at this stage would be to ignore it, and correct it with water changes once you hit the 30 day mark and the system has done it's initial cycle.

Once things begin to stabilize, and you can track alkalinity, calcium and magnesium together.

 

[johnj]

There may be some precipitation going on somewhere. I doubt it's from the rock.

There is a fairly wide margin to work with between them, but there is a link between all three major parameters and solely focusing on one while ignoring the other two could also be a problem. What are your calcium and magnesium levels at?

Alkalinity is unimportant to an initial cycle. Your best bet at this stage would be to ignore it, and correct it with water changes once you hit the 30 day mark and the system has done it's initial cycle.

Once things begin to stabilize, and you can track alkalinity, calcium and magnesium together.

I did a water change 40gal on my 160 gal start of last week because nitrates was 40ppm
I was only dosing alkalinity to bring my dkh up so that I don't have to do massive water change when nitrite had gone

my calcium is 421 with Hannah and mag is 1435

 

[W1ngz]

Is it possible that alkalinity was low to start with in the new water? It's not clear to me when the water change happened relative to your testing and dosing.

 

[Sabellafella]

my tank is 24 days into cycle using doc tims one and only and ammonia " Still got nitrite at around 0.3-0.6 and 25 nitrate"

but wy does my tank consume alkalinity with no coral/fish ? it went down as low as 5.6 dkh so added 143ml 10 days ago to bump upto 7.3 dkh " I added another 44ml of red sea foundations B alkalinity last night whot calculator said would get me upto 8.2 dkh" After checking 30 minutes after dosing" it only went up to 7.6 dkh
But did 2 Hannah checks today and alkalinity has gone down to 6.9 dkh ?

whots going on with tank!

This is very common although I don't know the the mechanics to its but the entire nitrogen cycle process down to nitrates - all those bacteria consume carbonate alkalinity. I'm sure in one of many articles you can find the mechanics to how it works

 

[lapin]

my tank is 24 days into cycle using doc tims one and only and ammonia " Still got nitrite at around 0.3-0.6 and 25 nitrate"

but wy does my tank consume alkalinity with no coral/fish ? it went down as low as 5.6 dkh so added 143ml 10 days ago to bump upto 7.3 dkh " I added another 44ml of red sea foundations B alkalinity last night whot calculator said would get me upto 8.2 dkh" After checking 30 minutes after dosing" it only went up to 7.6 dkh
But did 2 Hannah checks today and alkalinity has gone down to 6.9 dkh ?

whots going on with tank!

I had the same thing happen when I started my new tank. Alk went up and down for about 2 months. Then it stablized and dropped at a steady rate to below 7.3. I used baked baking soda to bring it back up to around 8.7 to 9. At around the 4 month time frame I got my calcium reactor on line and that coupled with 10% water changes every week keeps it around 9.

 

[Quietman]

Ditto. Would bump up on WC (yes, I did cycling WC) and then I added a few ml of All for Reef just to see what would happen (cycling is boring) - stabled it right out at 8.0 but didn't dose regularly or anything until I was getting ready for corals. Without the All for Reef it hung out around 7.5-7.8. No idea what the mechanism that causes that.

 

[johnj]

Is it possible that alkalinity was low to start with in the new water? It's not clear to me when the water change happened relative to your testing and dosing.

on the 11th this month my ammonia was 0.15-0.25 nitrite 0.25 I checked alkalinity at was 5.3 dkh
on 14th I added 140ml of red sea foundation liquid alk " checked 3 hour later and was 7.7 dkh
on 15th checked alkalinity and said 7 dkh .7 drop from night before
on 16th I changed 40gals of tank water with red sea blue at a dkh 8.2
also put socks and carbon in cups in sump and added brightwells no3 xport block also started skimmer
Alkalinity was 7.3 dkh with salifert and 7.1 dkh with Hannah

on 17th my alk was still 7.3 dkh same
on 19th my alk was still 7.3 dkh
on 20th my alk was 7.2 dkh and did calcium check at 421 on Hannah and mag was 1470
on 22nd I added 44ml of red sea foundations alkalinity whot calculator said to raise up to 8.2 dkh
went up to 7.7 dkh only

today I did test and got 6.9 dkh (done twice on Hannah) and 7.3 on salifert

iv made notes so this is how it has happened

 

[W1ngz]

This is very common although I don't know the the mechanics to its but the entire nitrogen cycle process down to nitrates - all those bacteria consume carbonate alkalinity. I'm sure in one of many articles you can find the mechanics to how it works

Found it:
For each ammonia molecule converted into nitrate, one hydrogen ion (H+) is produced. If nitrate is allowed to accumulate to 50 ppm, the addition of this acid will deplete 0.8 meq/L (2.3 dKH) of alkalinity.

However, the news is not all bad. When this nitrate proceeds further along the nitrogen cycle, depleted alkalinity is returned in exactly the amount lost. For example, if the nitrate is allowed to be converted into N2 in a sand bed, one of the products is bicarbonate

http://reefkeeping.com/issues/2004-12/rhf/index.php

 

[Sabellafella]

Found it:
For each ammonia molecule converted into nitrate, one hydrogen ion (H+) is produced. If nitrate is allowed to accumulate to 50 ppm, the addition of this acid will deplete 0.8 meq/L (2.3 dKH) of alkalinity.

However, the news is not all bad. When this nitrate proceeds further along the nitrogen cycle, depleted alkalinity is returned in exactly the amount lost. For example, if the nitrate is allowed to be converted into N2 in a sand bed, one of the products is bicarbonate

http://reefkeeping.com/issues/2004-12/rhf/index.php

Nice!

 

[johnj]

Found it:
For each ammonia molecule converted into nitrate, one hydrogen ion (H+) is produced. If nitrate is allowed to accumulate to 50 ppm, the addition of this acid will deplete 0.8 meq/L (2.3 dKH) of alkalinity.

However, the news is not all bad. When this nitrate proceeds further along the nitrogen cycle, depleted alkalinity is returned in exactly the amount lost. For example, if the nitrate is allowed to be converted into N2 in a sand bed, one of the products is bicarbonate

http://reefkeeping.com/issues/2004-12/rhf/index.php

that's good info but my nitrates have never got to 50ppm only once at 40 for few days till water change " and last 10 days or so its at 25ppm

 

[johnj]

Ditto. Would bump up on WC (yes, I did cycling WC) and then I added a few ml of All for Reef just to see what would happen (cycling is boring) - stabled it right out at 8.0 but didn't dose regularly or anything until I was getting ready for corals. Without the All for Reef it hung out around 7.5-7.8. No idea what the mechanism that causes that.

its at 30 days cycle this coming Saturday so may just do one 80 gal water change and add a fish or 2

 

[Quietman]

its at 30 days cycle this coming Saturday so may just do one 80 gal water change and add a fish or 2

Oh I just re-read that...I wasn't recommending water change. Just saying when I did them I saw a response and then back to being unstable or dropping - same with All for Reef addition. I don't think it's important until just before you're ready to add livestock.

 

[Sabellafella]

that's good info but my nitrates have never got to 50ppm only once at 40 for few days till water change " and last 10 days or so its at 25ppm

There is still other critters that take in alkalinity, every single person can relate to low alkalinity during a cycle. After a month or so all of that will fall closely back to normal.

You could dose if you'd like, I'd say after a month or so start using a bit of kalkwasser because that allows coraline algae to flourish.

 

[W1ngz]

that's good info but my nitrates have never got to 50ppm only once at 40 for few days till water change " and last 10 days or so its at 25ppm

50ppm is listed as a reference point, at which point the drop in alkalinity is as stated. If you produce only half that (25ppm of nitrate), then you'd have half of the corresponding drop in alkalinity. It's also not about the total quantity present, it's the quantity produced over time. If you do a water change when you are at 40ppm nitrate, to lower it to 20, and then a week later nitrate climbs back to 40, sure, you never had 50ppm at any given moment, but in total, you produced the original 40, and another 20 to get back to 40, a total of 60ppm.

All in all what the article is saying, is that a partially cycled tank consumes alkalinity. The final part of the nitrogen cycle, where alkalinity goes back up from the conversion of nitrate into nitrogen gas hasn't been achieved in your tank yet.

I'm going to go back to my original recommendation where you should ignore your alkalinity swings right now. A cycling tank is by nature unstable, and will take several months to settle down.

 

[johnj]

50ppm is listed as a reference point, at which point the drop in alkalinity is as stated. If you produce only half that (25ppm of nitrate), then you'd have half of the corresponding drop in alkalinity. It's also not about the total quantity present, it's the quantity produced over time. If you do a water change when you are at 40ppm nitrate, to lower it to 20, and then a week later nitrate climbs back to 40, sure, you never had 50ppm at any given moment, but in total, you produced the original 40, and another 20 to get back to 40, a total of 60ppm.

All in all what the article is saying, is that a partially cycled tank consumes alkalinity. The final part of the nitrogen cycle, where alkalinity goes back up from the conversion of nitrate into nitrogen gas hasn't been achieved in your tank yet.

I'm going to go back to my original recommendation where you should ignore your alkalinity swings right now. A cycling tank is by nature unstable, and will take several months to settle down.

got you know on above mate" so don't do anything till my nitrates are gone? they have bean stuck at a low 0.3 to 0.8 for 10 -14 days! then do big water change to get shut of nitrates
cannot believe that people cycle there tanks in 7 days with doc tims!