Stabilizing a tank (low Alk, hIgh nitrate)

[Mark_C]

New tank hit a bad place post completion of transfers.
With the loss of two crabs and a Tanakas wrasse, followed by the degeneration of some corals, I actually got off my ass an am doing some reefing.

Figured I would chart progression here, along with my reponses and numbers as I get the tank under control for either posterity, or to maybe show a newbie how to reign things in.
Of course, I'm always open to suggestions and learning as well.

Specs:
Tank is a 30g IM AIO, 36" long, 12" deep, 12" high
1.026 SG, 79F, skimmer, fuge with Marine Pure and Cheato, Red Sea Pro salt (black bucket)
25# established live rock, 8-10 small to medium sps, 2 small zoa colonies, 2 small montis, 1 small to medium scroll, 8 head trumpet, 1 small frogspawn.
Tomini tang, mandarin, lyre anthias, 2 mocha storms, 1 purple d-back, 1 pincushin urchin, 1 fire shrimp, a few misc crabs and snails

Sept 12
Ca - 450
Alk - 7.1
NO3 - 30+ (yes, off the charts on the Red Sea kit)

Performed 4g water change
Alk - 7.5

Removed a large filefish to reduce bioload (and he may well have been nipping on some corals).
Harvested out 60-70% cheato (removed decaying bits and opened up the good green stuff to light)
Add 30ml Microlift Special Blend to help reinforce tank bacteria
Slightly increased skimmer (to help reduce organic waste)
Changed filter floss (to prevent organic waste decomposition)
Feeding reduced to 50% (to lower introduced organics to tank)


Sept 13
Ca - ?
Alk - 7.5
NO3 - 30+

Performed 4g water change
Alk - 7.9

Add 5ml Seachem Reef Fusion 2 to boost Alk
Alk - 8.5 ( I know, steep climb, that RF2 boosted things quick)

Add 30g of Purigen to reactor to help control NO3 and reduce organics
Changed filter floss
Feeding reduced to 50%


Sept 14
Ca - 500
Alk - 8.3
NO3 - 25 (appx)

Performed 2g water change
Add 5ml Seachem Reef Fusion 2 to boost Alk
Alk - 9.0

Add 10ml Seachem Prime to help reduce NO3
Changed filter floss
Feeding maintained at 50% split to 2 feedings (am and pm)

With this volume it appears that a WC will raise Alk by 0.1 per gallon and RF2 will raise it by approx 0.1 per ml.
Hopefully it'll stay this simple. RF2 jumps Alk quick, going to run with WCs for slow Alk increase with NO3 reduction over next few days.


Sept 15
Ca - 480
Alk - 8.6
NO3 - 10

Increased filtering plus Seachem Prime seems to have taken NO3 down by 15, averaging 1ml of SCP to reduce NO3 by approximately 2ppm (working theory)

Performed 4g Water change (if theory is right, post WC I should be at 9.0 dKH)
Ca- 500
Alk - 9.0 (yeah, baby!) *In 30g, 1g of 1.026 Red Sea Pro will increase dKH by 0.1
NO3 - 10

Theory to bring down NO3 by 6-8ppm.
Dosed 4ml Seachem Prime
NO3 - 6 (appx 1.5ppm per ml this time, so speculating 1ml Prime reduces NO3 by 1.5-1.8ppm)

Sept 16
Ca - 480
Alk - 8.2
No3 - 8

Add 5ml Reef Fusion 2
Add 5ml Prime
Giving a shot at straight up chemical control here sand WC

Sept 17
Ca - ?
Alk - 8.1
NO3 - 8

Add 5ml Reef Fusion 2
Add 5ml Prime
Changed filter floss

Sept 16
Ca - ?
Alk - 8.1
NO3 - ?

Add 10ml Reef Fusion 2

 

[amado]

What salt are you using ?

 

[Mark_C]

Good question Red Sea Pro. It mixes in bucket at between 10.9 and 11.1 dKH.

 

[amado]

Yeah for a small tank. The Red Sea reef pro
Is too high. Since you have so little water volume any change will affect your numbers.

I would switch to a salt that has the numbers that you are looking for.

so if you want alk 8.5 find a salt that has those values

in a large system like I have I can use red sea pro and my system will not be effected by the 15% water changes.

 

[Mark_C]

I've got 2 big buckets from the big tank.
And they've been used for a weekly WC in this 30g for a few months, which doesn't explain the low dKH.
I'm guessing that if 1/2c of RSP in 1g of water hits 1.026SG and raises my dKH by .1, I should be able to manage my dKH adjustments by daily checking of Alk and using 1ml of the Seachem per .1 dKH off, then use the same adjustment for a weekly water change, substituting the amount of water to compensate for the loss in 0.1 dKH increments. That made sense in my brain, does it in type?

 

[amado]

I've got 2 big buckets from the big tank.
And they've been used for a weekly WC in this 30g for a few months, which doesn't explain the low dKH.
I'm guessing that if 1/2c of RSP in 1g of water hits 1.026SG and raises my dKH by .1, I should be able to manage my dKH adjustments by daily checking of Alk and using 1ml of the Seachem per .1 dKH off, then use the same adjustment for a weekly water change, substituting the amount of water to compensate for the loss in 0.1 dKH increments. That made sense in my brain, does it in type?

the problem is not alk. From my Expirience
Alk will always get consumed.
The problem is mag And calcium they can easy get out of wack.

 

[hcker99]

So here's my .02 , SLOW DOWN Your chasing numbers and that were you're going to get in trouble. I wouldn't worry about the nitrates as that's not what's killing corals. My money is on the alk. I would just do WC and then very slowly dose alk as needed. I would be testing MAG as well as that's what's working as the binder.


I would be doing 5 gallon WC's in that size tank. Doing that may even keep your numbers in line without having to constantly dose.

 

[Mark_C]

Current plan is to stop dosing and use WC to maintain Alk.
As of 9pm tonight, Alk is at 9.0 dKH, would like to stabilize it there.
Still need to bring Nitrates down but the Purigen, overskim, decreased food, and daily floss changes should help over the next week or two.
I know 1g of water increased dKH by 0.1 so for the next week, to help maintain Alk and decrease NO4, I'll do WCs in place of dosing. I'll do 2 WC per week based on Alk pre-change ( if I'm down to 8.8 dKH, I'll do a 2g WC to bring up approx 0.2, etc).
Other stuff should fall in line, but will dose as required for Ca and Mg if the need ever arises.

 

[TomReefer]

Hey Mark, good idea on your water changes. You might want to increase the size of the changes as well. 20% changes 2 times weekly. Allow your chaeto to keep growing. Maybe increase your photoperiod on your refugium. Are you using Kalkwasser in your ATO? That will help stabilize your Alk quite a bitGood luck.

 

[Mark_C]

Bump for Sept 15 numbers.
Looks good.

So, In 30g of water:
1g of Red Sea Reefer at 1.026 (1/2c) will raise Alk by 0.1dKH
1ml of Seachem Reef Fusion 2 will raise Alk by 0.1dKH
1ml of Seachem Prime will decrease NO3 by approximately 1.5ppm

Now to determine if WCs to maintain Alk will cause Ca to increase too much, in which case I may need to dose Reef Fusion 2 with low Alk and norm/high Ca situation while falling back to WC with low alk and low Ca situation