Water Temperature Fluctuations to Mimic Seasons?

[CJO]

Apex Classic Dashboard has seasonal tables fo sunlight, moonlight to coincide with seasonal changes but their temp tables show 78.5 year round - just an FYI

I think this has changed. I used the temp table to vary my temperature by the seasons several years ago. I didn't notice any real impact over 2-3 years.

 

[Doctorgori]

I can understand chemical stability as that never changes in the ocean, but temperature does vary somewhat even in the tropics but to a less degree.
I can see stressed new arrivals needing matched temps but healthy fish and corals?
I seriously doubt a degree or 2 over 24 - 48 hrs really stresses anything. Obviously temp stress varies per species. Just IME

 

[josephxsxn]

Something I recently learned that I didn't know was that some tanks do much better handling dino outbreaks at higher 82f+ temperatures.

 

[Ben Pedersen]

My water temps range from around 73 in Jan and Feb to around 82 in Aug and Sept. It has been this way for 10+ years. The coldest it has been is 68 and the warmest 85. I prefer to keep it between 74 and 80, but the room that the tank is in and the climate where I live cause seasonal temperature fluctuations.

I have not seen adverse affects on fish or corals. I have noticed the SPS looks more metallic / iridescent in colder water and grow slower. Some fish don't like the cold. I notice that my convict tang does not like it. I feel like I need to give him a sweater.

At water tempratures below 70, some corals start to loose color. If water temps fall lower than 69 for more than a day, coral starts looking bad but recover if temps increase. If you are wondering how I know, I had a broken heater in February. My tank was at 68 for 1.5 days. After replacing the heater, all corals fully recovered.

At warmer temps, coral grows faster but are not as colorful (in my opinion). As Josephxsxn metioned, my RBTA splits like clockwork if the temp rises above 81. I know some venders use warm water to split their nem stock.

Bacteria are also more active in warmer water.. As long as you have good bacteria, that is good. If you have bad bacteria, not so good.

In the real world, reef water temps fluctuate greatly. If your tank fluctuates between 73 and 80 seasonally, you will likely not notice much change.

For those wondering what types of coral live through 68 degree water... My tank below:

 

[Ahogue21]

There has been at least one scientific research project carried out which shows coral's are hardier to stressor events with less chance of bleaching and so on if fluctuations in temperature are allowed to occur, as opposed to corals that are kept in very stable temperature environments

The main goal of the research if i remember correctly ( it was about 10 years ago I was reading the research papers) Is to find/create these hardier corals/zooxanthelae combo's to then help repopulate with these hardier specimens the decimated areas of reef due to bleaching events due to climate change

"That which does not kill us makes us stronger"

Ive always thought this in regards to people chasing numbers in there tanks and trying to always keep stuff spot on i remember a conversation i had a few months ago with a guy complaining his heater couldnt hold a .3 degree swing

My thoughts always been there is a thing such as to stable and then when you do get a variance it doesnt go well

Last week i took down my big tank and put everything into a temp tank 2 days later i cleaned up all the wiring and when i woke up in the morning went to rearrange some coral and water was cold.....checked it 68 degrees now i have all softies but nothing was upset plugged heater back in and over the next 12hrs brought it back up to 78 and didnt have a single loss fish or coral

 

[mindme]

I've been thinking about mimicking seasons in my tank by allowing my tank temperature to fluctuate every 4 months by 2 degrees (i.e. December = 74 degrees, March = 76 degrees, July = 78 degrees). Has anyone tried this? I know that coral and fish spawning is tied to the seasons, so for breeding purposes this might be important, but for the general reefer are there any potential advantages/improvements that could be induced by mimicking seasons?

Sounds interesting to me, and I'm not sure why this would be considered "unstable" by some. It's not like you are talking about larger swings in temps, just gradual declines.

The only thing I would wonder is if that much temperature difference is needed. I've never looked before, but maybe take a peak at temperature changes at reefs over the year and go from that, rather than just doing 2 degrees for all.

I've read where lighting can cause spawning, so this in addition to all those things may aid in that. Good luck, hope it works for you.

 

[Kal93]

Sounds interesting to me, and I'm not sure why this would be considered "unstable" by some. It's not like you are talking about larger swings in temps, just gradual declines.

The only thing I would wonder is if that much temperature difference is needed. I've never looked before, but maybe take a peak at temperature changes at reefs over the year and go from that, rather than just doing 2 degrees for all.

I've read where lighting can cause spawning, so this in addition to all those things may aid in that. Good luck, hope it works for you.

Thanks for the suggestion!

Looking at the range of ocean surface temperatures where my fish are collected, I dropped my tank temp from 79 to 72 degrees in the AM (and 70 degrees at night). This change took place over 5 days. It's been a week and my fish and coral have no changes in behavior or coloration (albeit I only have a few softies and 1 torch; SPS may not be so tolerant).

I'll update this thread as I continue to play around with temperature.

 

[HuduVudu]

Maybe this can help.

I lived on the reef for three years and snorkeled and dove when I could. First off I am going by what I felt in the water. I can in no way verify the actual temperature, but I can make some reference to how water feels on say may arm now. That said. Some observations. Water temperature is affected by currents not air temperature. Some areas have sluggish currents and if it is sunny will heat up to bathtab temperatures. I assume this to be upper 80s lower 90s. This can be pretty dramatic over small areas. Literally 10 to 20 feet apart will experience what I would guess to be a 10 to 15 degree temperature difference. Depth plays a huge role. The deeper you go the colder it gets. For illustration. If you are at 5 feet and it is comfortable 80ish degrees, then going to 30 feet will be less comfortable maybe 70ish degrees. Fish can and do move up and down these gradients. Coral not so much. Some gradients are stark. I think that it is documented this zonation. Apparently it screws with sonar. Where I was at there were two seasons. Rainy (monsoon) season and dry season. Most of rainy season you could not dive/snorkel because of the visibility. These two seasons were approximately 6 months each. The temperature for monsoon will be an educated guess, because I never really did anything in the water at those times, first because the current was dangerous and second because the visibilty was garbage. When I say low visibility I mean you can't see your hand in front of your face. With all of the water turbulence my guess is the water temperature must be lower. One because the sun could not heat the water at the surface and two because of all of the water upwell from deep water.

Coral vs. Fish. Fish are more mobile and will move through many different temperature zones, but have more of a choice into which zone they go. Mostly though I don't think the fish worry to much about this they are always going to be driven by food. Coral wil be successful or not in various zones. A very warm zone near where I snorkeled was totally dominated by macro algae.

Sea water oxygen saturation is very dependent on temperature (and salinity). I think that this can play a role.

Just some thoughts FWIW.

 

[sculpin01]

Yearly water temperature charts are available and easy to find. For instance, here is St. Croix:

Sea water temperature Saint Croix today | USVI

Sea water temperature forecast and historical data for Saint Croix. Today's sea surface temperature report. Average monthly sea temperature and surf forecast

seatemperature.info

If you assume the water temperature being measured is shallow, subtracting 2-3 degrees from each monthly average will give you a reasonable range for corals in 5-10 meters of water. In addition, day-to-night ocean temperature fluctuation is in the range of 1.5 - 3 degrees F which is easy to program in Apex. If you are planning on trying to induce spawning (from what I have read) 79.5 F is the minimum temperature to trigger spawning. 84.5 F is the temperature at which bleaching becomes a high risk, below that you are pretty safe.

[Output Heater]
Fallback OFF
Set OFF
If Output DayHeat = ON Then ON
If Output NightHeat = ON Then ON
If Tmp > 84.0 Then OFF
If Tmp < 70.0 Then ON

[Virtual Output DayHeat]
If Tmp < RT+-0.2 Then ON
If Tmp > RT+0.2 Then OFF
If Time 18:00 to 06:00 Then OFF

[Virtual Output NightHeat]
If Tmp < RT+-2.2 Then ON
If Tmp > RT+-2.0 Then OFF
If Output DayHeat = ON Then OFF

My season table:

 

[JohnnyDreadlock]

I leave my tank without a heater. I don’t worry about temp unless it’s starts moving three degrees or more from the usual numbers.

 

[Uncle99]

My water temps range from around 73 in Jan and Feb to around 82 in Aug and Sept. It has been this way for 10+ years. The coldest it has been is 68 and the warmest 85. I prefer to keep it between 74 and 80, but the room that the tank is in and the climate where I live cause seasonal temperature fluctuations.

I have not seen adverse affects on fish or corals. I have noticed the SPS looks more metallic / iridescent in colder water and grow slower. Some fish don't like the cold. I notice that my convict tang does not like it. I feel like I need to give him a sweater.

At water tempratures below 70, some corals start to loose color. If water temps fall lower than 69 for more than a day, coral starts looking bad but recover if temps increase. If you are wondering how I know, I had a broken heater in February. My tank was at 68 for 1.5 days. After replacing the heater, all corals fully recovered.

At warmer temps, coral grows faster but are not as colorful (in my opinion). As Josephxsxn metioned, my RBTA splits like clockwork if the temp rises above 81. I know some venders use warm water to split their nem stock.

Bacteria are also more active in warmer water.. As long as you have good bacteria, that is good. If you have bad bacteria, not so good.

In the real world, reef water temps fluctuate greatly. If your tank fluctuates between 73 and 80 seasonally, you will likely not notice much change.

For those wondering what types of coral live through 68 degree water... My tank below:

Absolutely amazing.
Love it.

 

[DeniseAndy]

I have had my tank pretty stable for over 12 years and it will be lower in the winter (75 to 77) and higher in summer 77 to 80. I do have heaters and chillers to accomplish this. I have done this with SPS, LPS, Softies and gorgs. My fish spawn, my clams are good, urchins spawn, but not my corals. My nems rarely do either.
My daily swings are usually within 1-2 degrees. Not vary much over 24hours.