Neptune Aquatics

finicky coral

newfly

newfly

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I'm a bit lost here. Is this normal? Some corals are happier than others. Not sure why

The following corals is doing very well (growing nicely and good coloration)
- Green slimer
- Monti Sentosa
- Rainbow Monti (died back due to nudis but started to grow/encrusting again)
- rock flower nems

No growth but not dying. Good coloration
- blue stag
- Pocillopora
- zoas
- orange digi

So so
- Frogspawn - only open 50% for the past few months

Dying ... Tissue receding
- Green birdnest
- Stylo
- chalice


Parameters have been very stable for the past month.

Alk: 8.8
Cal : 425
Mg: 1320
Phosphate : 0.04
Salinity : 1.025-1.026
 
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Some corals like some systems better than others. Instead of chasing all corals, I try to get little frags to see what works, then grow those out. For example, the WD frag I picked up from TLR 6 months ago hasn't done anything but maybe recede a little at the base. Other things grow like weeds.

Also, when a portion of coral starts dying, it can cause coral polyps near it to get unhealthy and potentially die.

There is also tank/system maturity that can help. I found that at the 1.5 year mark, I stopped killing as many frags, even though I didn't really change anything major. At 2 years, things got even easier and sick corals will come back to health in my tank now.
 
Coral reefer said:
Lots of factors. Light and flow come to mind.
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What puzzle me is the corals are next to each other, on the same rock shelf, within 2-3 inch part but 1 can thrive and another just barely. For example, the birdnest and monti sentosa is literally next to each other. Not touching but close by. I assume the light and flow is very similar. I also assume monti and birdnest have similar requirement for light and flow.

All my corals are still "frags size" not colony.
 
iani said:
I know you mentioned phosphates but what is your nitrates.
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I have GHA issue, maybe not yet taking over the tank, but still significant amount. My measurable nitrates are near 0, btw 0-5 ppm. I did dose NItrates a month or so back but that feed the GHA and encourage the growth even more. Stop dosing and the cuc is slowly making a dent.

Short answer is my nitrate is very low, but i suspect its due to the GHA.
 
Here may lie your problem. Coral need nutrients to photosynthesize like algae does as well. If your nutrients are that low, your ALK needs to come down. Most running ULNS have ALK around 7. Also generally coral cannot take as much light at lower nutrients.
 
Yes! Get dirtier water! Feel free to grab mine at the end of the month before I replace my gfo rector. PO4 @ .4 and Nitrates over 30, lol
 
I am aware i may have nitrate issue, My plan is to keep the status quo for the next month or so, let the cuc do their job and make a dent at the GHA. Then either increase feeding or dose nitrate.

if indeed my issue is low nitrate, then its still surprising some coral species like monti can do well where else others just dying.

Reducing Alk is a good suggestion. I read about it before. I just finally to get alk stable at 8.8. I supposed reducing Alk to ~7 over1 month period is safe? I am very nervous messing with Alk after the swing.

I'm dosing soda ash 10.8ml a day. I'll reduce 1ml/day every week and see the impact. Is this game plan sound? Right now i'm matching cal to alk dosing 1-1. I'll reduce ca dosing as well.
 
You’ll get lots of opinions about Alk level. The ocean is about 7, but it has an essentially infinite reserve capacity- no matter how much gets used by coral it’ll still be 7. In a reef tank, you can’t keep it perfectly stable, even with frequent testing and dosing, because you don’t have an infinite reserve and because testing is not completely reliable. If you are doing a good job, it’ll vary +/- 0.5, a variation that in and of itself is fine. However, Alk of 6.5 is too low. So lot of people think of 8 as a good target because 7.5-8.5 is a good safe range with some room for error either way.
 
JVU said:
You’ll get lots of opinions about Alk level. The ocean is about 7, but it has an essentially infinite reserve capacity- no matter how much gets used by coral it’ll still be 7. In a reef tank, you can’t keep it perfectly stable, even with frequent testing and dosing, because you don’t have an infinite reserve and because testing is not completely reliable. If you are doing a good job, it’ll vary +/- 0.5, a variation that in and of itself is fine. However, Alk of 6.5 is too low. So lot of people think of 8 as a good target because 7.5-8.5 is a good safe range with some room for error either way.
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My point was that for a tank to be successful with undetectable nitrates his Alk should also be lower. ULNS is a different beast than an aquarium with some nutrients. I keep my Alk at 8.2-8.5 but I also have ~20 ppm of nitrates. If I were shooting for lower nutrients I would bring down my Alk.
 
iani said:
My point was that for a tank to be successful with undetectable nitrates his Alk should also be lower. ULNS is a different beast than an aquarium with some nutrients. I keep my Alk at 8.2-8.5 but I also have ~20 ppm of nitrates. If I were shooting for lower nutrients I would bring down my Alk.
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Yes, people who run their Alk at 10 and have ultralow nitrate/phosphate to try to optimize both growth and color make their systems less stable. Alk of 8 is good for low nitrate and phosphate; it is the recommendation of most companies in this business and many many successful reefers. I only rarely see 7 recommended, for the reasons I said (even though seawater is about 7).
 
JVU said:
Yes, people who run their Alk at 10 and have ultralow nitrate/phosphate to try to optimize both growth and color make their systems less stable. Alk of 8 is good for low nitrate and phosphate; it is the recommendation of most companies in this business and many many successful reefers. I only rarely see 7 recommended, for the reasons I said (even though seawater is about 7).
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That is not true. https://www.reef2reef.com/threads/highest-alk-for-ulns.756163/
There are multiple threads like this and people often times recommend an Alk of 7 for ULNS.
 
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For ULNS I would stick to 7ish and not into the 8.0+ range, especially if your nitrates are undetectable. I've even been in the 6.5 range for ULNS. Once you're above the 8.0+ range, you'll see tips start to burn and the onset of STN.
 
Ok, fair enough guys, but this isn’t a thread about ULNS from an advanced reefing perspective in tightly controlled systems, this is a thread about why are some of newfly’s corals doing poorly and others ok in the context of him having trouble stabilizing his tank parameters, and not trying for ULNS. His phosphate is on-target. His nitrate is too low because of algae consumption not intentionally (ie unstable). I think in this case, I think a recommendation of shooting for 8 is safer than a recommendation of shooting for 7 because it gives more room for error.

I don’t think 7 is wrong, just more likely to cause problems when it drifts down. And by the way, I don’t see any indication that Alk is the problem here from his description of what corals are doing well vs not.
 
It's all somewhat connected, mainly through stress to corals. With low nutrient levels, in this case nitrates, you want to keep things in balance. The reason why lower alk levels is suggested isn't because we're looking at an advanced topic, but rather it's a way to reduce stress to the corals. Dropping it down would help and 8 is definitely recommended. At the same time, I would suggest looking at upping nitrates.

For a tank so new, I wouldn't worry too much about algae for the most part unless it's way overgrown to a point where it's choking out corals. I would up nitrates levels (manual dosing, taking the skimmer offline for a bit instead of running 24/7, feeding fish more (only to the degree that the tank isn't overfed where it's left to contribute to the phosphates levels), feeding more pellets instead of frozen (unless you're really good at adhering to rinsing out frozen food routinely), etc.).

IMO, algae isn't a concern since it's a natural progression for the most part and adding nutrients, nitrates in this case, will help the tank "mature" in due time, while reducing stress to the corals.
 
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