decline in coraline growth and zoo health in my nano

[Dan Thrash]

I have a 12 gal nanocube that has been set up for 1 year now. i have mostly zoos with some rics and one open brain. the brain and rics are great, the zoos recently haven't been too happy. the first 6-8 months in the tank, everything exploded with life. but the past two months my zoos have all been half closed for the most part and my coraline growth has mostly stopped.

i dont dose anything, just weekly 2-3 gal waterchanges with Reef Crystals, and i admit, i dont test as often as i should. i tested today and ammonia and nitrites are 0, nitrates are almost 0, ph is 8.4, cal is 355 and alk is 8 dkh, temp is kept around 80.5 deg. i have 72W of PCs and a maxi 900 for flow.

any recommendations on what i can do? i guess i should start by raising my calcium. is alk ok? or should i raise that?

thanks for the help,
Dan

[Shooter7]

When was the last time you changed your bulbs? Your Ca and alk are a bit on the low side as well. I know once I start getting into numbers like that, my coralline starts showing displeasure as well.

[Dan Thrash]

i have one 10k bulb which i just replaced less than a month ago and two actinic bulbs that could really use a change.

[kathainbowen]

The calcium is definitely too low. Bring that on up to 400-450ppm, and that should help, especially with the coraline.

The other thing is, I've noted some biocubes can be low on flow when packed with liverock and unassisted with by small powerheads, and zoos are just magnets for mulm. When covered or impeded by excessive dust and mulm, zoos, as well as other polyps like star polyps or yellow polyps, will close up and stayed closed. Try either a gentle dusting off with a powerhead, baby medicine dropped, or turkey baster to see if you can knock off some accumulated dust.

See if that helps, but definitely bring the calcium up and slightly raise the alk.

[Dan Thrash]

yeah, you know, i've been thinking of getting rid of the cube because i feel like i dont get good flow in many parts of the tank...either that or redo my rock. i could add another powerhead in the tank, but i can't find one small enough so it doesnt take up the whole tank and look bulky. i do blow off the rocks with a turkey baster.

[Doglover_50]

If your cube is a standard bran (jbj, etc...), the flow problem is completely solvable. If you are using stock pump, dump it in favor of a maxijet 900 or 1200. Also, if you check online--foster and smith, etc...., there are tiny pumps for sale that could be hidden in rock.
put up a thread about your flow issues and the pros will give you good answers!
otherwise have you cleaned your pump lately?

[dastratt]

Hey what's mulm? Must be the cr*p that comes out of my zoos when I baste 'em . Another way I find to get mulm (?) out of them (and cyano off of them which also causes problems) is to "wave" at them with my hand or scraper when I'm scraping the tank.

I agree ca is low note that for ca and alk to be in balance ca should be raised in a balanced way. How do you control ca and alk levels? Both will tend to decline. Here's a couple of good articles:
1) on correcting ca
http://web.archive.org/web/200211270...v2002/chem.htm
2) maintaining ca and alk
http://www.advancedaquarist.com/issues/feb2003/chem.htm

Edit: After reading that you dont supplement I would consider two part solution. I don't think its very expensive for a nano considering what we spend on this hobby. Though reef crystals has good ca the coraline will use it up

[kathainbowen]

Mulm, I must admit, is a rather antiquated term I still find cute and use when basically referring to "that random crap and debris in your tank." The actually definition would be "Mulm is the undecomposed fish wastes and other solid matter that accumulates in the aquarium." So, both officially and unofficially, mulm is basically random crap. It's one of those terms I somehow picked up while working with freshwater tanks, and I just can't break myself from referring to what is, essentially, organic wastes and sendiments as "mulm."

[Dan Thrash]

thanks for the info everyone. i'm going to start dosing a two part...probably B-ionic for now and see if i can raise my levels and maintain them.

[PSam]

Stop dosing. Measure your levels. Use this: http://reef.diesyst.com/

Then get what you need to add added, and then test to see what you need to add in order to maintain. On a 12g, it isn't likely to be much 2 part. You should be able to fix it fairly quickly and simply.

I'd raise alk first, very slowly. Then Ca. Just use the B-Ionic (not dosing both parts - use the alk part until your alk gets up, when it is, use the Ca part to get your Ca up).