Cycled tank - not increasing nitrate

[ilikefish69]

Hello - I have 75 gallon tank, 3 months. Tank has cycled, went through ammonia and nitrite and now doesn't have any. The nitrate "spike" happened 20-40 PPM, and then it slowly started lowering. Still no ammonia or nitrite, but nitrates are basically remaining around 20 PPM not increasing or decreasing for about 2 weeks.

I have one yellowtail damsel in the tank. Is there not enough fish to maintain the bacteria population? I don't want to have to re-cycle my tank when I put in a second fish. Or put in a new first fish, as I learned after bringing home the yellowtail (LFS highly recommended the fish to me) that it does not play nicely with others.

Do I need to put more FISH in this tank? Everything I read says to take things sloooooooooooooow. But I am thinking with 75 gallons of water, there isn't enough ammonia being produced to maintain a bacteria colonization.

 

[iMi]

You're totally fine. One small fish in such a large tank would produce low nitrates. Just add a few more fish. You can dose some bacterial to help the nitrifying process along during these changes.

If you see aggression from the damsel, take it out for a day and put it back in the tank. That works for me. I have two damsels and two dotty's living in perfect harmony in 65 gallons. It's all about landscaping and how much room you have. There are some fish you should definitely add last, like coral beauty, etc.

 

[New&no clue]

What are you using for nutrient removal, (skimmer, water changes, live rock). If you have a fish and no ammonia your tank is cycled.

 

[ilikefish69]

I haven't changed any water, but it evaporates probably a gallon a day and I'm putting in tap water to top it off, so I think that is currently taking place of my 'water changes' and I have three hang on the back filters that have mechanical filtration pads and some carbon running through it.

Why is the coral beauty the last fish to add to the tank?

 

[ScubaFish802]

As others said above.. I would also say safe to add more fish. But as you already mentioned, safe to increase the load slowly rather than a big hit all at once

 

[FourPawz]

A Definitive Answer: Do You Need RO/DI Water for a Saltwater Aquarium or Reef Tank?

Check this out.

 

[92Miata]

The tank has been up for 3 months with fish. You're way past cycling. Stop worrying about it.


And yes, buy more fish.

 

[ilikefish69]

The tank has been up for 3 months with fish. You're way past cycling. Stop worrying about it.


And yes, buy more fish.

I am the proud owner of a pair of ocellaris clownfish. Been in about 2 weeks. No coral/anemone for them yet They are WEIRD but a lot of fun to watch. Still not getting nitrates above 10 PPM. Ordered a sweet RODI kit off Amazon, will be here tomorrow. Going to put 15 gallons of new RODI water in it tomorrow evening, no matter how low the nitrates are. These fish need new water, I just know they do.

 

[EeyoreIsMySpiritAnimal]

I am the proud owner of a pair of ocellaris clownfish. Been in about 2 weeks. No coral/anemone for them yet They are WEIRD but a lot of fun to watch. Still not getting nitrates above 10 PPM. Ordered a sweet RODI kit off Amazon, will be here tomorrow. Going to put 15 gallons of new RODI water in it tomorrow evening, no matter how low the nitrates are. These fish need new water, I just know they do.

Periodic water changes are almost always a good thing. Just make sure you match salinity relatively closely (becomes more important the larger the water change). Assuming you have no coral yet... Fish won't care about calcium, alkalinity, etc.
As for your nitrates, your number seems fine. As others have said, as long as you don't increase your bioload too quickly, your system (bacteria) will adjust to the added waste. If you want to be extra cautious, you can always add a capful of Stability or other shelf-stable bacteria (as opposed to the concentrated, refrigerated kind) with each new fish to boost the nitrifying bacteria.

You're doing great... Keep learning and asking questions

 

[ilikefish69]

Periodic water changes are almost always a good thing. Just make sure you match salinity relatively closely (becomes more important the larger the water change). Assuming you have no coral yet... Fish won't care about calcium, alkalinity, etc.
As for your nitrates, your number seems fine. As others have said, as long as you don't increase your bioload too quickly, your system (bacteria) will adjust to the added waste. If you want to be extra cautious, you can always add a capful of Stability or other shelf-stable bacteria (as opposed to the concentrated, refrigerated kind) with each new fish to boost the nitrifying bacteria.

You're doing great... Keep learning and asking questions

I'm just spacing out the next fish, I reeeeeeeeeeeeeally want a yellow eyed kole tang, but have to wait for the tank to have algae for it to eat. Not sure who the next fishy is going to be.

Salinity is matched perfectly, I add water conditioner to it and then stir, and then salt. got one of those fancy drop the water on the blue glass and look through the telescope, so it's much easier than the first time I was in the hobby and had a floating thermometer I had to wait for the water to be completely still, and I try to lower and turn the pumps on and pour the new water into the pumps so it gets spread throughout the tank pretty quickly and there aren't pockets of new water in the old water.

I'll probably introduce a mushroom coral first, they seem to be an easier first coral.

 

[EeyoreIsMySpiritAnimal]

I'm just spacing out the next fish, I reeeeeeeeeeeeeally want a yellow eyed kole tang, but have to wait for the tank to have algae for it to eat. Not sure who the next fishy is going to be.

Salinity is matched perfectly, I add water conditioner to it and then stir, and then salt. got one of those fancy drop the water on the blue glass and look through the telescope, so it's much easier than the first time I was in the hobby and had a floating thermometer I had to wait for the water to be completely still, and I try to lower and turn the pumps on and pour the new water into the pumps so it gets spread throughout the tank pretty quickly and there aren't pockets of new water in the old water.

I'll probably introduce a mushroom coral first, they seem to be an easier first coral.

I think you're describing a refractometer. If so, please be sure to calibrate it often.
As far as algae for the kole, yes, they will help with the algae in your tank, but feeding quality herbivore or omnivore flakes, pellets, etc, will be your best bet.

 

[ilikefish69]

I think you're describing a refractometer. If so, please be sure to calibrate it often.
As far as algae for the kole, yes, they will help with the algae in your tank, but feeding quality herbivore or omnivore flakes, pellets, etc, will be your best bet.

I calibrated the refractometer upon receiving it... I didn't realize it needed to be recalibrated. Man this forum is full of knowledge. Now I have to sit here at work for another 3 hours and be super nervous. Maybe it is a good day to take off early?

 

[Lavey29]

I calibrated the refractometer upon receiving it... I didn't realize it needed to be recalibrated. Man this forum is full of knowledge. Now I have to sit here at work for another 3 hours and be super nervous. Maybe it is a good day to take off early?

They need to be calibrated before every use.

 

[92Miata]

They need to be calibrated before every use.

They only need to be recalibrated before every use if they're of very low quality.

Mine has been about 6 months since it was adjusted. Still bang on exactly 35ppt against the calibration solution. And mine's by no means an expensive one.

 

[Lavey29]

They only need to be recalibrated before every use if they're of very low quality.

Mine has been about 6 months since it was adjusted. Still bang on exactly 35ppt against the calibration solution. And mine's by no means an expensive one.

Sorry, disagree.... this is one example from UC Davis:

Refractometers should be calibrated at the beginning of each use and, depending on how many samples are being measured, periodically throughout the sampling process.

My refractometer gets off slightly with temp changes. I use a digital one now.

 

[Randy Holmes-Farley]

Most people find they do not change much between a single use, but if yours does, then it needs frequent calibration. Otherwise you can let the time between calibrations get longer and longer until you seem to detect it needs it that often based on it being off by more than you are comfortable with.

 

[Lavey29]

Most people find they do not change much between a single use, but if yours does, then it needs frequent calibration. Otherwise you can let the time between calibrations get longer and longer until you seem to detect it needs it that often based on it being off by more than you are comfortable with.

Does temp affect accuracy and or humidity Randy?

 

[Randy Holmes-Farley]

Does temp affect accuracy and or humidity Randy?

Humidity should have no impact.

A refractometer with ATC (automatic temperature compensation), as most do, are not supposed to be impacted by temp changes within a reasonable range (something like 65 to 85 deg F, if I recall correctly), but how well they accomplish that will vary.

A refractometer without ATC will vary a lot with temp changes.

 

[Lavey29]

Humidity should have no impact.

A refractometer with ATC (automatic temperature compensation), as most do, are not supposed to be impacted by temp changes within a reasonable range (something like 65 to 85 deg F, if I recall correctly), but how well they accomplish that will vary.

A refractometer without ATC will vary a lot with temp changes.

Thank you

 

[bnord]

I haven't changed any water, but it evaporates probably a gallon a day and I'm putting in tap water to top it off, so I think that is currently taking place of my 'water changes' and I have three hang on the back filters that have mechanical filtration pads and some carbon running through it.

Why is the coral beauty the last fish to add to the tank?

Off to a good start, and that is a lot of evaporation - have you looked into Auto Top Off devices?