What alk level produces your best colors?

[Felixc]

I see many posts/polls asking levels of KH people keep their reefs at, but I am wondering how many of those responses indicated whether or not their sps corals were colorful. I've been closely monitoring my KH for 3 months, test alk twice a week, and my finding is that a KH range of 7.5-8.5KH produced the most vibrant colors than at any other levels, and at the same time producing good growth rate. I practice over skimming, use Bio Pellets, GFO, Carbon, automatic dosing pumps, strong lighting, heavy fish load, and bi-weekly water changed just to give you a better idea.

IMO, the biggest challenges in maintaining this precise level is based on a couple factors; the accuracy of the test kit available to us and the constant depletion/comsumption of KH by coral growth and filter medias. I've being using 3 different brands of test kits and all 3 read differently (7KH to 11KH), this part is the most frustrating aspect of trying to achieve the desire level. I have settled with the average of the test kits. Another is KH depletion by using GFO/Bio pellets, because the depletion rate varies from day one vs day 30, along with that is the constant coral growth comsuming at an exponential rate daily. For these reasons, I am finding that I have to weekly adjust my dosing pumps to achieve the steadiness and balance.

With all that aside, at what KH level do you achive the best colors out of your sps?

 

[Znut Reefer]

9.0 -9.3

 

[seashark]

my tank responds good to 8.5- 9.0

 

[jcolletteiii]

so are you close to an ULNS? That might explain optimal ALK being on the low side. I ran GFO and biopellets with the alk around 8.5 - 9 for awhile, and colors suffered BADLY. I have a prostrata that almost completely bleached. I have no fish, so nutrients are quite low. I stopped running GFO about two weeks ago, and things are responding positively - some color coming back. I've also let the ALK drop a bit - I'm down in the 8 region now.

 

[Felixc]

my next question is, do you believe the results you get from your test kit? If so, explain. If not, how far off do you think it is? + or - 1,2,3? My kits were repeatedly tested at:
TM = 7KH
ELOS = 8.5KH
Salifert = 11KH

This is the most troubling aspect of it all, it's nearly impossible to achieve the steadiness of your parameters within a 1 KH when there is this large discrepancy amongst the test kits. Maybe I am just too meticuluous, I like it steady.

 

[Felixc]

so are you close to an ULNS? That might explain optimal ALK being on the low side. I ran GFO and biopellets with the alk around 8.5 - 9 for awhile, and colors suffered BADLY. I have a prostrata that almost completely bleached. I have no fish, so nutrients are quite low. I stopped running GFO about two weeks ago, and things are responding positively - some color coming back. I've also let the ALK drop a bit - I'm down in the 8 region now.

I don't believe I am close to ULNS. There are no nuisan algae, and all the corals are nicely colored while running GFO and Bio Pellets together for the past 9 months. In my 140g total system, I run 1L of Bio pellets and 1.5" of GFO in TLF reactor changed monthly. Roughly 4 tangs, 12 anthias, 2 butterfly, 8 firefish, and 2 angelfish. 3 Feedings a day.

 

[jcolletteiii]

Did you run the salifert test kit against the reference soln in the test kit?

 

[rikers1271]

9 dkh. i like to think of CA, Kh, and GH as coordinates. 1 part. is meaningless

 

[catman78]

I run mine around 8.00. I'm pretty close to ULNS.
Zeo tanks run around 7.5, 8 @ most.

I use a Lamotte test kit for Alk. Easy to read. As far as how accurate?
who knows.

If your salt mix is lower/higher then your target then make sure to test a few days after wc.

 

[wfournier]

my next question is, do you believe the results you get from your test kit? If so, explain. If not, how far off do you think it is? + or - 1,2,3? My kits were repeatedly tested at:
TM = 7KH
ELOS = 8.5KH
Salifert = 11KH

This is the most troubling aspect of it all, it's nearly impossible to achieve the steadiness of your parameters within a 1 KH when there is this large discrepancy amongst the test kits. Maybe I am just too meticuluous, I like it steady.

I've seen the same thing with different test kits, I think what you need to do is pick one and stick to it. It's frustrating and I wish I could find out which of my kits it "correct" but that's what I've been living with. I've settled on using a Lamotte kit because I feel that the tablets they use are more consistent than some of the droppers on other kits.

 

[beeker]

i shoot for an alk of 7-10 and honestly i don't know which one produces better color in my 200g

my sps in my 29g had great color and i used to run my alk in that tank at 12-13DKH not ever going to run it that high again but i never noticed any ill effects from doing so

Elo's is the most accurate kit that i have found for Alk

I have used Salifert, API in the past both were wayyyy off and led to me killing a few sps, i will never use anything other than Elo's when it comes to test kits i feel they are the most precise kits out there, though they are expensive it's better than killing over 100 dollars worth of stock

 

[MammothReefer]

the stable ones. The longer my alk stays consistent the more I see my sps start to colour, as soon as I see flux, I notice halting/browning. I shoot for 8 w/elos test kit.

https://spreadsheets.google.com/pub...ZFhsTXBGTUFZellSWTZ3QkhiLVE&hl=en&output=html

 

[beeker]

I'll try keeping it at 8 for the next month or two and see how it goes, i'm carbon dosing and amino dosing now anyways so i never get above 9 as it is since i know how bad sps can react to higher alk and carbon

 

[Felixc]

Did you run the salifert test kit against the reference soln in the test kit?

Yes I test it against the standard and it is within the tolerance. I have borrowed three Salifert kits from different friends and all show similar results. In the past I've tried following the Salifert results, leaving my KH at 8 and I see a major decline in coral color and growth. When I bump it up to 10KH, everything is happy again. I've concluded that the Salifert is reading 2-2.5 KH higher that what it should be.

 

[jc-reef]

I agree with MammothReefer ^^^. I have seen beautiful tanks with Alk at 8 and also at 11. IMO, once you found your range where your corals are growing nicely, the more stable the Alk swings, the better. Corals adapt pretty amazingy. I read many stories with people trying to 'chase' numbers which end up throwing something else off and ultimately being detrimental to the live stock. The KISS rule does work.

 

[caliking]

Keep my alk between 8-12. As long as it stays steady the coral are happy and growing. I test every other week and adjus the dosing pumps accordngly. it generally stays beween 9-10. My coral growth is rapid. I Place frags in the tank an they encrust to the LR in 2weeks.

Best colors between 9-10.

Ca 450, Mg 1350, Dkh 10, Po4 0.05, Ph 8.2

 

[Felixc]

No doubt stability is the key to maintaining the nice colors. You also must know where your test results lies. Someone running their tank at 10KH or 11KH, might actually be running at 8KH or 9KH, or on the high end 12KH or 13KH , it depends on the accuracy of the test kit. I do agree if you figure how much to compensate for the difference, then just stick with that refrence point for testing, but it all comes down to knowing that reference point to really achieve the correct levels.

 

[abrian]

I keep my Alk steady at 8.3dkh using a Salifert kit, testing weekly (or more often) at the same time of day, and adjusting my dosing pumps as needed when it starts to dip. Now I do not know that the Salifert is accurate and I might actually be lower than that, but I figured shooting for 8.3 gave me a bit of a buffer in case the kit reads high. What is more important is keeping the Alk as steady as possible I figure, and lacking a reliable kit I just picked a 'safe' target and keep it there.

 

[chercm]

what about for zeovit tank ?

 

[LifeAquatic]

I shoot for 8-9.