Coral growth and change in alkalinity

[Pimba]

So if I raise my alkalinity to say 11dkh and it is still 11 after a week or so that means the corals are not growing? I raised Ca 420ppm and that hasn't dropped either.

I don't visually see they are growing either for months now. I have no3 about 50ppm and po4 about 0.6ppm. could it be because of that ?

 

[Spare time]

You need to list a lot more about you tank, including the lights, the spectrum, the settings, the flow, etc. Alk is just one component.

 

[Spare time]

Phosphate that high could slow down growth. That is about 6x the usual recommended maximum phosphate value people recommend here (usually betweeen 0.02/0.03 and 0.1ppm)

 

[Pimba]

Here's a pic of the tank to get an idea. It doesn't have lots of coral: a few hammers, elegance, goniopora (green one doesn't open fully) and some gsps.

In terms of lights. I have 2 kessil a160wes on the following schedule.

11am = turns on at 0 color 5% intensity
11am-3pm = ramps up to 25% color 70p intensity
3pm to 9pm = stays at 70p intensity
9-10pm = ramps down to 0 intensity

 

[Spare time]

I definitely think you can run the intensity at 100%. The color is fine, that is personal preference when it comes to kessil lights (kessil logic makes this possible) Just slowly move it up to that. Do you use macroalgae? I think that would definitely help you out in getting the water cleaner.

As for the corals, elegance and hammers can be very slow growing corals. Hammers often are very slow until the colony gets large (depends on the type of hammer).

 

[Ancient Mariner]

A young, immature reef will have low Ca/alk uptake as conditions are not right for coral or coralline algae growth. Mine took 1.5 years with SPS to take off with Ca and alk demand. From having to turn off my Ca reactor to having to max out the Ca reactor and add additional dosing with 2 part Ca/alk took 2 years. Maybe your reef just needs to mature a little more.

 

[Pimba]

Do you use macroalgae? I think that would definitely help you out in getting the water cleaner.

I have a small clump of chaeto in my sump. It's been in the sump for 2 weeks now and haven't taken off yet. It's really frustrating even my GSPs are not growing fast.

 

[Spare time]

I have a small clump of chaeto in my sump. It's been in the sump for 2 weeks now and haven't taken off yet. It's really frustrating even my GSPs are not growing fast.

What light do you have over it? How often do you do water changes?

 

[revenant]

Phosphates.... run some GFO to lower the po4.. don't overdue it.. need .03 in at least.. and tank time...

 

[Forty-Two]

So if I raise my alkalinity to say 11dkh and it is still 11 after a week or so that means the corals are not growing? I raised Ca 420ppm and that hasn't dropped either.

I don't visually see they are growing either for months now. I have no3 about 50ppm and po4 about 0.6ppm. could it be because of that ?

Nitrates are quite high - usually need to be around 5-10 ppm. Phosphate is also very high. It needs or be around .05 ppm.

when my Phos was at .2 ppm - my Favias were very unhappy - as were most of my corals and didn’t grow much. Now at .05 I’m seeing some good growth.

 

[thatmanMIKEson]

So if I raise my alkalinity to say 11dkh and it is still 11 after a week or so that means the corals are not growing? I raised Ca 420ppm and that hasn't dropped either.

I don't visually see they are growing either for months now. I have no3 about 50ppm and po4 about 0.6ppm. could it be because of that ?

Absolutely

 

[thatmanMIKEson]

Here's a pic of the tank to get an idea. It doesn't have lots of coral: a few hammers, elegance, goniopora (green one doesn't open fully) and some gsps.

In terms of lights. I have 2 kessil a160wes on the following schedule.

11am = turns on at 0 color 5% intensity
11am-3pm = ramps up to 25% color 70p intensity
3pm to 9pm = stays at 70p intensity
9-10pm = ramps down to 0 intensity

Not enough light

 

[Pimba]

So could it be because of lights (running 2 kessil a160wes at 70% intensity for 6 hours) or high nutrients?