High nitrates and phosphates but no algae? Why not?

[mta_morrow]

So for 17 months or so, nitrates and phosphates have been steady. NO3 10-16, PO4.03-.1. No algae.

about a month ago I added a diamond goby. Dyson has been a good goby and has has exceeded my expectations! My sand bed is pristine!
But all that digging up of a 17 month old sand bed now has nitrates at 60+ and phosphates at .29
Water changes are starting again and I will get those back to where I want them. No big deal.
But......why no algae?

 

[anon9896]

I only know this
since I've been keeping some macro algaes in my tank, even if I toss a frag with bryopsis
bryopsis, cyano, dinos, what not goes to hell.

 

[mta_morrow]

Bump.

 

[Katrina71]

Do you have a healthy fuge?

 

[mta_morrow]

I have a reactor that is growing GHA, but that’s all.

 

[Silent]

So you do have algae growing in your system, it's just controlled. That's a big reason some grow in a refugium so it outcompetes algae in the DT.

 

[anon9896]

I wonder if all of this has to do with the fact that algaes need C02 to grow.
in an old sand bed you might have some gas that temporarly kicks out the C02.
Can we correlate a tank aeration and the algae growth in it.
I've been studying C02 concentration in enclosed spaces for a while, I can tell you that many people have very intoxicating habits.
As a rule of thumb a low ph can be an 'indicator' as there is too much C02 in the tank.
I did check on my phyto culture to see if there is any C02 release and It doesnt gives me out of the ordinary numbers.
Following.

 

[Silent]

Ph will let us know how much CO2 is in the tank. If this is your theory OP will have quite high pH.

 

[mta_morrow]

using an API test kit, my Ph is 7.8-8.0

 

[anon9896]

Is your tank on day cycle ?

 

[mta_morrow]

Is your tank on day cycle ?

I’m not following the question. What do you mean?

 

[Katrina71]

So you do have algae growing in your system, it's just controlled. That's a big reason some grow in a refugium so it outcompetes algae in the DT.

+1

 

[anon9896]

Well on day time photosynthesis of the algaes rises Oxygen in a tank while lowering the C02
On night time it's the contrary.
That is one of the main reason why people use lights at night on the fuge to compensate ph drop.
I would not be worried to see c02 levels around 7.8 on night cycle but on day time.. it's a little low in my experience. but again there could be other factors, like I said it'S an indicator.

 

[Dana Riddle]

Liebig's Law of the Minimum: Plant growth is limited by the least available nutrient, even if other nutrient levels are high.

 

[mta_morrow]

Well on day time photosynthesis of the algaes rises Oxygen in a tank while lowering the C02
On night time it's the contrary.
That is one of the main reason why people use lights at night on the fuge to compensate ph drop.
I would not be worried to see c02 levels around 7.8 on night cycle but on day time.. it's a little low in my experience. but again there could be other factors, like I said it'S an indicator.

OK......I do run my reactor at night, opposite the main display. And also my HVAC draws outside air in when heating or cooling. Perhaps this helps as well.

 

[LC8Sumi]

Very interesting. I’ll follow this. I don’t think some GHA in a reactor would be enough to compensate for that high NO3/PO4 values enough to prevent algae in the DT. There must be something else going on.

 

[saltyhog]

Great question. I think there are probably multiple reasons this occurs. A couple that I thought of ......

1. It's possible that high nutrients are not the 'cause' of algae problems...only fuel to the fire when there is a lack of biodiversity. A healthy tank can often get away with what we used to think of as dangerous levels of nutrients.

2. Great algae control in place. My tank is a good example. If you look at my tank you won't see a speck of nuisance algae despite my NO3 level of 10 and PO4 level 0.08-0.14. However if you take a peek into my overflow you will see gobs of hair algae and some bubble algae. In my DT the only place I can find it is on the top of the return nozzel( which is about 1/2" under water and unreachable for my tang) and behind a rock that is resting against the overflow and doesn't allow access. Otherwise my CUC keeps it clean as can be.

Interesting to see if the lack of algae persists over time! Great thread!

 

[WallyB]

So for 17 months or so, nitrates and phosphates have been steady. NO3 10-16, PO4.03-.1. No algae.

about a month ago I added a diamond goby. Dyson has been a good goby and has has exceeded my expectations! My sand bed is pristine!
But all that digging up of a 17 month old sand bed now has nitrates at 60+ and phosphates at .29
Water changes are starting again and I will get those back to where I want them. No big deal.
But......why no algae?

LOL..

Are you hoping for Algae?

I could be your lighting. If low on white and red, and you only have blue, algae won't grow as much.
If you want algae turn up your red, and watch it explode. Red/Blue is what makes Algae Scrubber grow algae.

But you do raise an interesting point.

I do have an algae scrubber, and at first it was like a Algae Factory. 100+ grams of Algae every two weeks.
Then after a while it slowed down, and now barely grows any (5 grams maybe a month).
My nitrates are around 25, and PO4 was around 0.3 and still no Significant Algae.
I wondered about that. I wonder what's stopped the Algae scrubber since it wasn't N&P. Something else must be missing. I thought Potassium, but it's on spec.

 

[Oliver d]

Interesting I have more or less the same situation no algae in the display but also dont have a refugium in my sump No3 stays more or less at 20 and the Po4 at+0.09.

 

[Quietman]

tick, tick, tick....