Help with coral health!!

Lexy40 · Apr 9, 2024

Hi everyone,

I am very new to the world of marine aquariums and corals and this is also my first time posting a question, so please be gentle with me!

My partner and I set up a tank about 6 months ago...he had a marine aquariaum previously so I assumed that he knew all that was needed and I was just along for the ride! So after we installed the tank he declared that he was never very good at 'all of the technical science bits', so that could be my department!

We have a 550litre tank (including sump) and added the TMC Eco Reef. Understanding that this is not the same as live rock we added the pure reef balance bacteria balls and let that all circulate for a bit. we started testing water about a week later and watched the tank cycle through from high ammonia to high nitrite and then high nitrate and then eventually settle down. After about 2 weeks we added some hermit crabs, Pearson shrimp who have all been very happy and all fine.

Since then we have added some other livestock, we now have about 8 hermit crabs in total, 1 peppermint shrimp, 1 fire shrimp, 2 peacock wrasse, 2 chalk gobies, 1 dot dash blenny, 1 parrot wrasse, 1 blue cleaner wrasse, 1 blue eyed tang, 1 sandsifting starfish and one red/ orange starfish, 4 emerald crabs and 4 anemones... We also had a beautiful mandarin which I was not convinced the tank was ready for as I had read that you should have a mature tank of at least 2 years, but my partner really wanted one so went for it anyway and he was OK for quite a while, we were feeding live copepods , but sadly he did not make it in the end.

Anyway, that's the back story (apologies if I have gone into too much detail, just wanted to give all of the relevant info!) so more rcently we have started adding corals, in February we added a pulsing xenia (which is doing fine and growing nicely), a feather duster (seems happy) and (I think) a candy cane coral. At this point the only water parameters that we had been testing were pH, ammonia, nitrite and nitrate, so I don't know what any other ones were when we started adding corals.

Since then my partner has gone a bit mad with the corals and has added in quite a few extra corals of both hard and soft varieties (I'm not great with the IDs of them I'm afraid), but some of them did not seem too happy, especially the hard corals...I had read that calcium and magnesium in particular were important for corals, so we got test kits for these and started testing...calcium was extremely low, way off the chart, something like 180ppm! Magnesium was slightly higher than the optimal I think it was around 1350ppm. So we started adding Red Sea brand calcium but had read that too much at once can shock the coarals, so initially we were only adding 10ml per day but then with a bit more research realised we could do more, so we were adding 50ml per day...the calcium is now up to 410ppm so much closer to where it should be, but the hard corals are still declining, some have lost what seems like an outer 'skin' and are now completely white.

So my question to you all with your superior experience is, what do you think we are doing wrong? Do you think the initial low calcium caused the corals to die off and even after the levels came up in the water it was too late to recover the corals, or do you think its something else entirely?

My partner was feeding the Red Sea Coral food daily, but I read that too much might not be good for them so we are doing that every other day now.

Any insights/ advice would be greatly appreciated, and apologies for such a long rambling post!

eliaslikesfish · Apr 9, 2024

first note: start testing your alkalinity ASAP and get that to about 9dkh and start testing your phosphates and make sure that hovers between .05-1.0ppm.

I’m gonna go ahead and assume the “hard corals” are SPS. (post pictures though so we can confirm)
SPS corals require a very stable environment to thrive and fluctuations in water quality will easily upset them. Additonally you need to have the correct lighting and flow for them to thrive. Grab a little wave maker if you don’t already have one and/or make sure the SPS are getting sufficient flow. for the lighting, I would buy or borrow a PAR meter from your LFS as the good ones are expensive and make sure where the SPS are placed, the reader measures about 200-300. You should also think about getting a doser as well for the alkalinity, calcium, and magnesium once you figure out how much your reef tank consumes on a daily basis as this can get annoying quickly… Hope this helps and below is what I personally would try to keep your parameter at or around:

Salinity: 1.025
Ph: 8.0
Alkalinity 8-9dkh
Magnesium: 1350ppm
Calcium 420-430ppm
Phosphates: .05-1.0ppm
Nitrates: 5-20ppm range has always worked great for me.

Mr. Mojo Rising · Apr 9, 2024

I don't really see anything wrong except that you are going a little fast. The mandarin fish, and your starfish, and sps are all 'advanced' livestock. You lost the mandarin and sps, and I'm sorry, but the starfish will likely die too, they usually don't survive in newer tanks.

There is more to keeping corals than just 4 or 5 parameters. Water quality is important, lighting and flow, husbandry, rodi water, nutrient levels, biodiversity, quality test kits, etc.... its all part of it, and it takes time.

Keep researching, it is a really important part of success in this hobby.

Cell · Apr 9, 2024

What salt are you using and what salinity? What test kits? Your calcium measurement at 180ppm seems like a testing error.

Alkalinity, calcium, nitrate, and phosphate are your primary parameters to monitor. Mg, not so much.

Lexy40 · Apr 10, 2024

eliaslikesfish said:
first note: start testing your alkalinity ASAP and get that to about 9dkh and start testing your phosphates and make sure that hovers between .05-1.0ppm.

I’m gonna go ahead and assume the “hard corals” are SPS. (post pictures though so we can confirm)
SPS corals require a very stable environment to thrive and fluctuations in water quality will easily upset them. Additonally you need to have the correct lighting and flow for them to thrive. Grab a little wave maker if you don’t already have one and/or make sure the SPS are getting sufficient flow. for the lighting, I would buy or borrow a PAR meter from your LFS as the good ones are expensive and make sure where the SPS are placed, the reader measures about 200-300. You should also think about getting a doser as well for the alkalinity, calcium, and magnesium once you figure out how much your reef tank consumes on a daily basis as this can get annoying quickly… Hope this helps and below is what I personally would try to keep your parameter at or around:

Salinity: 1.025
Ph: 8.0
Alkalinity 8-9dkh
Magnesium: 1350ppm
Calcium 420-430ppm
Phosphates: .05-1.0ppm
Nitrates: 5-20ppm range has always worked great for me.

Thank you so much for taking the time to reply!
We do have a wave maker, I think the flow is pretty good across the tank. We will definitely look into getting a PAR meter, I we have been wondering how it can be measured and I didn't realise you could buy them.
We do have a doser as well but haven't set it up yet as we haven't been sure on the amounts to use.

I forgot to say that I also started testing for KH and phosphates when we started to see a decline in the corals. Phosphates are 2ppm but KH has been really high off the chart it was 21 a couple of weeks ago, now 16. I understand most if the other parameters, how they relate to each other and how to alter them, but KH I am a bit lost on to be honest...what is the best way to bring it down? We are doing 10% water change weekly.

Cell · Apr 10, 2024

Your testing is off. 16 alk and 180 calcium doesn't make sense.

crazyfishmom · Apr 10, 2024

Which salt mix do you use and how often do you perform water changes?

My very first thought after reading your post is that instead of dosing anything, making several small water changes over the course of two to three weeks (every other day or every two days) should get you back to a healthy baseline.

There’s a lot we don’t know about your tank despite all the great info you’ve provided. Would you be able to take some quick pictures of your entire setup? Also, please post your lighting schedule and light specifications.

Best of luck and hang in there! Lots of great people on this forum that are always willing to help.

twentyleagues · Apr 10, 2024

I agree with the others if you dont have par readings, what type of light are you using? If more than 1 how many?
What salt are you using? What sg do you mix it to? How are you measuring?
Pics? Pics? Did I mention pics? This will help to determine rock structure, where corals are placed, and a multitude of other info.
What is the footprint of the tank? While volume can be helpful footprint is more so. Lots of shapes can encompass 550l.
What test kits are you using? Same for all or multitude of different brands?
I like to give back story on issues I have too. Unfortunately a lot of really helpful people here just want facts and will skim what you have typed to see if facts are supplied, if they dont see hard number they may not have an answer or may not supply an answer based on lack of information. I get why this is the way it is so many new threads and a lot of them start the same. Not bashing. I do it too. I have tried to reign it in some. You see I can get wordy....lol
I am unsure if I said this already a picture is worth a thousand words. Pic can supply so much needed info they are not just for showing off your cool tank.
BTW Welcome!

eliaslikesfish · Apr 10, 2024

Lexy40 said:
Thank you so much for taking the time to reply!
We do have a wave maker, I think the flow is pretty good across the tank. We will definitely look into getting a PAR meter, I we have been wondering how it can be measured and I didn't realise you could buy them.
We do have a doser as well but haven't set it up yet as we haven't been sure on the amounts to use.

I forgot to say that I also started testing for KH and phosphates when we started to see a decline in the corals. Phosphates are 2ppm but KH has been really high off the chart it was 21 a couple of weeks ago, now 16. I understand most if the other parameters, how they relate to each other and how to alter them, but KH I am a bit lost on to be honest...what is the best way to bring it down? We are doing 10% water change weekly.

what test kits are you using? I would get some hanna checkers because as some have stated your calcium and alk shouldn’t be 180 and 16 -please post some pictures of your tank and aquascape, coral placement as well

Lexy40 · Apr 10, 2024

Mr. Mojo Rising said:
I don't really see anything wrong except that you are going a little fast. The mandarin fish, and your starfish, and sps are all 'advanced' livestock. You lost the mandarin and sps, and I'm sorry, but the starfish will likely die too, they usually don't survive in newer tanks.

There is more to keeping corals than just 4 or 5 parameters. Water quality is important, lighting and flow, husbandry, rodi water, nutrient levels, biodiversity, quality test kits, etc.... its all part of it, and it takes time.

Keep researching, it is a really important part of success in this hobby.

Thank you so much for taking the time to reply.
Yes I had read that Mandarins were advanced, but my partner was convinced it would be fine (!) The starfish seem quite happy to be honest, they have definitely grown since we had them...what signs would you look for that might indicate that they are not doing well?

Lexy40 · Apr 10, 2024

twentyleagues said:
I agree with the others if you dont have par readings, what type of light are you using? If more than 1 how many?
What salt are you using? What sg do you mix it to? How are you measuring?
Pics? Pics? Did I mention pics? This will help to determine rock structure, where corals are placed, and a multitude of other info.
What is the footprint of the tank? While volume can be helpful footprint is more so. Lots of shapes can encompass 550l.
What test kits are you using? Same for all or multitude of different brands?
I like to give back story on issues I have too. Unfortunately a lot of really helpful people here just want facts and will skim what you have typed to see if facts are supplied, if they dont see hard number they may not have an answer or may not supply an answer based on lack of information. I get why this is the way it is so many new threads and a lot of them start the same. Not bashing. I do it too. I have tried to reign it in some. You see I can get wordy....lol
I am unsure if I said this already a picture is worth a thousand words. Pic can supply so much needed info they are not just for showing off your cool tank.
BTW Welcome!

Hi, thanks for taking the time to reply.
We are using the iLumenAir 900 and salt is Red Sea Coral Pro mixed with RO to a salinity of 1.024
I'm using the API test kit for pH, ammonia, nitrate, nitrite, phosphate and KH and we have the Salifert tests for Calcium and Magnesium. We did repeat the Ca test several times as it seems so off, but it was the same each time.
Apologies for not including all of the required info...I thought I had covered everything but as a newbie you don't know what you don't know!
Most recent tests were as follows
Temperature 25.2
Salinity 1.024
pH 8.2
Ammonia 0
Nitrite 0
Nitrate 5ppm
Phosphates 2ppm
KH 16
Calcium 410
Magnesium 1350
Thanks for the welcome and your input...I think I have attached a photo of the tank, hadn't figured out how to do that before!

Lexy40 · Apr 10, 2024

eliaslikesfish said:
what test kits are you using? I would get some hanna checkers because as some have stated your calcium and alk shouldn’t be 180 and 16 -please post some pictures of your tank and aquascape, coral placement as well

I'm using the API test kit for pH, ammonia, nitrate, nitrite, phosphate and KH and we have the Salifert tests for Calcium and Magnesium.
We have just ordered the hanna checker for Calcium, waiting for that to come. Would you suggest getting the same for other parameters? Are they more accurate?
Calcium was 180 to start with but is now up to 410 since adding Red Sea calcium liquid over the last couple of weeks. KH was even higher than 16 initially, but has reduced a bit. I have added a picture above, not sure if I need to add it again but I'll try just in case!

eliaslikesfish · Apr 10, 2024

Lexy40 said:
I'm using the API test kit for pH, ammonia, nitrate, nitrite, phosphate and KH and we have the Salifert tests for Calcium and Magnesium.
We have just ordered the hanna checker for Calcium, waiting for that to come. Would you suggest getting the same for other parameters? Are they more accurate?
Calcium was 180 to start with but is now up to 410 since adding Red Sea calcium liquid over the last couple of weeks. KH was even higher than 16 initially, but has reduced a bit. I have added a picture above, not sure if I need to add it again but I'll try just in case!

absolutely. definitely get the hanna testers for alkalinity, nitrates, phosphates and magnesium. it will save you a lot of time and frustration in the future. the api test kits are not accurate.

love the starfish just hanging out on the glass btw hahaha

twentyleagues · Apr 10, 2024

So your light is pretty good from the review I just read. From all accounts it looks to be a legit powerful light, I do wonder at its ability to provide the correct spectrum for all coral health. The main power comes from the 6500k leds. Years ago many people used 6500k mh so it should grow coral. At what intensity do you have it set? you may be cooking corals especially at that high alk and relatively low nitrate and what I am assuming still is a incorrect phosphate reading. You may want to switch up the salt you are using for something with a lower alk redsea coral pro mixes at 12 dkh.

Lexy40 · Apr 13, 2024

twentyleagues said:
So your light is pretty good from the review I just read. From all accounts it looks to be a legit powerful light, I do wonder at its ability to provide the correct spectrum for all coral health. The main power comes from the 6500k leds. Years ago many people used 6500k mh so it should grow coral. At what intensity do you have it set? you may be cooking corals especially at that high alk and relatively low nitrate and what I am assuming still is a incorrect phosphate reading. You may want to switch up the salt you are using for something with a lower alk redsea coral pro mixes at 12 dkh.

Thank you so much for replying and researching the light! I will have to check with my partner and get back to you about the light settings, as he deals with that bit!

Thanks for pointing out about the salt, that makes a lot of sense, we will look at swapping for the lower dkh one.

Just realised that there's something else which is probably contributing to the high alkalinity, we have been adding a pH buffer to the water as our pH previously was in the 7's, but I've just seen that it has a KH buffer as well (photo attached) so that's not good!! Can anyone recommend a pH buffer which doesn't also alter KH??

I tested the pH of our tap water when we started having issues and found that it's 3.5, which is why we have to keep adding the pH buffer in the first place!

Thanks again for your help

twentyleagues · Apr 13, 2024

Lexy40 said:
Thank you so much for replying and researching the light! I will have to check with my partner and get back to you about the light settings, as he deals with that bit!

Thanks for pointing out about the salt, that makes a lot of sense, we will look at swapping for the lower dkh one.

Just realised that there's something else which is probably contributing to the high alkalinity, we have been adding a pH buffer to the water as our pH previously was in the 7's, but I've just seen that it has a KH buffer as well (photo attached) so that's not good!! Can anyone recommend a pH buffer which doesn't also alter KH??

I tested the pH of our tap water when we started having issues and found that it's 3.5, which is why we have to keep adding the pH buffer in the first place!

Thanks again for your help

Dont quote me on this as I am not a chemist I do not believe there is a ph buffer that will not also raise alk.

So there are some things you can do to see if your low ph is caused by co2 in the source water. Take a sample of your source water and using an air pump and air stone or just an airline aerate it preferably outdoors to limit home co2 air levels test before and after to see your ph. Temp will affect the reading also try keeping it close, but you are not really worried about accuracy at this point just to see if there is a noticeable difference before and after aeration.

Using tap water isnt the worst ( its kinda bad really) but RO/DI is much preferred. There could be other stuff in the tap water that will affect your parameters, could also be lending to your kh issue. If your ph issues are co2 related and in a reef tank they usually are about the only reason you can do things like, Run an outside air line to your skimmer air intake, incorporate a co2 scrubber into your air intake of skimmer. just opening windows in the room can help but that is temporary. Get an air exchanger but that is not cheap.

I have kind of the same issue with ph mine sits around 7.8 it does fluctuate up to 8.1 maybe at times in tank. I was having some issues with my premixing of saltwater, I checked a few things and nothing was adding up. I assumed it was co2 levels in the basement where I store my ro/di and premixed saltwater, so I purchased a digital co2 monitor. Stupid thing cost me $175 and took a month to get. Guess what? I dont have high levels of co2 in the basement or fish tank room at this time....maybe when the heat was running more often but not currently. Fish room sits at 475 ppm average which is good, almost outside levels, the room is filled with plants so I am not that surprised. Basement was around 550 average over 5 days this thing does that, tracks highs and lows and averages them via an app. The main living area over a week was in the 900s average, makes sense my mom lives with me and her 150lb dog and my 2 cats and myself, an old gas stove so pilot lights creating co2 also. I am still stumped I guess and now out $175 but I guess its better to know than not. Like I said though I am not a chemist so those levels are good in the basement and fish room according to air quality reports, not so much in the rest of the house. Will those levels have an affect on tank ph? I am unsure. I was thinking I'd see a very high number and come to the conclusion well thats obviously it, but nope.

Lexy40 · Apr 14, 2024

twentyleagues said:
So your light is pretty good from the review I just read. From all accounts it looks to be a legit powerful light, I do wonder at its ability to provide the correct spectrum for all coral health. The main power comes from the 6500k leds. Years ago many people used 6500k mh so it should grow coral. At what intensity do you have it set? you may be cooking corals especially at that high alk and relatively low nitrate and what I am assuming still is a incorrect phosphate reading. You may want to switch up the salt you are using for something with a lower alk redsea coral pro mixes at 12 dkh.

Thank you so much for replying and researching the light! I will have to check with my partner and get back to you about the light settings, as he deals with that bit!

Thanks for pointing out about the salt, that makes a lot of sense, we will look at swapping for the lower dkh one.

Just realised that there's something else which is probably contributing to the high alkalinity, we have been adding a pH buffer to the water as our pH previously was in the 7's, but I've just seen that it has a KH buffer as well (photo attached) so that's not good!! Can anyone recommend a pH buffer which doesn't also alter KH??

I tested the pH of our tap water when we started having issues and found that it's 3.5, which is why we have to keep adding the pH buffer in the first place!

Thanks again for your help

Lexy40 · Apr 14, 2024

twentyleagues said:
Dont quote me on this as I am not a chemist I do not believe there is a ph buffer that will not also raise alk.

So there are some things you can do to see if your low ph is caused by co2 in the source water. Take a sample of your source water and using an air pump and air stone or just an airline aerate it preferably outdoors to limit home co2 air levels test before and after to see your ph. Temp will affect the reading also try keeping it close, but you are not really worried about accuracy at this point just to see if there is a noticeable difference before and after aeration.

Using tap water isnt the worst ( its kinda bad really) but RO/DI is much preferred. There could be other stuff in the tap water that will affect your parameters, could also be lending to your kh issue. If your ph issues are co2 related and in a reef tank they usually are about the only reason you can do things like, Run an outside air line to your skimmer air intake, incorporate a co2 scrubber into your air intake of skimmer. just opening windows in the room can help but that is temporary. Get an air exchanger but that is not cheap.

I have kind of the same issue with ph mine sits around 7.8 it does fluctuate up to 8.1 maybe at times in tank. I was having some issues with my premixing of saltwater, I checked a few things and nothing was adding up. I assumed it was co2 levels in the basement where I store my ro/di and premixed saltwater, so I purchased a digital co2 monitor. Stupid thing cost me $175 and took a month to get. Guess what? I dont have high levels of co2 in the basement or fish tank room at this time....maybe when the heat was running more often but not currently. Fish room sits at 475 ppm average which is good, almost outside levels, the room is filled with plants so I am not that surprised. Basement was around 550 average over 5 days this thing does that, tracks highs and lows and averages them via an app. The main living area over a week was in the 900s average, makes sense my mom lives with me and her 150lb dog and my 2 cats and myself, an old gas stove so pilot lights creating co2 also. I am still stumped I guess and now out $175 but I guess its better to know than not. Like I said though I am not a chemist so those levels are good in the basement and fish room according to air quality reports, not so much in the rest of the house. Will those levels have an affect on tank ph? I am unsure. I was thinking I'd see a very high number and come to the conclusion well thats obviously it, but nope.

Ok so if there is no pH buffer that doesn't also alter KH and assuming that what we are adding is at least contributing to the high KH, would you opt for a slightly lower pH (currently 8.2) to allow the KH to hopefully drop alongside it? Or maybe switch the dosage on it so it's not such a sudden change to shock the tank and halve what we've been adding?

I did wonder about CO2...at one point we did have lots of tiny bubbles on the rocks, especially in the top area of the tank. At the time we had quite a lot of green algae on the rocks but since we got out blue eyed tang and some emerald crabs the algae has pretty much gone and so have the bubbles along with it.

Our tank is in the living room where we also have a log burner stove (as far away from each other as possible). We have a cooler installed which kicks in if temp raises as we were worried about overheating, but I had not thought of the CO2 in relation to this so that's super helpful.

We do have an air stone, so we'll try that test, thank you for that info.

Sorry I should have been clearer about the tap water...we do make our own RO water for our salt water, I just meant that I tested the original source tap water out of curiosity and couldn't believe how low it was as apparently 7-9 is average. I did get a water quality report from our water supplier and apparently everything was within range, although the report didn't actually give pH levels.

Thanks so much for your input, I'll check those things and report back!