Is my tank crashing

[skipb1956]

This may be a bit long I apologize, but want to give as much background as possible.
This morning my neon dottyback, red wrasse and banded coral shrimp were found dead in my tank, and my 2 clownfish seem a bit sluggish.
I have a 36 gall tank that has been running for 8 months. I have been wrestling with high nitrate and phosphate issues for months. I didn't worry to much as all my fish and corals seemed happy and healthy. I do have issues with algae and in an attempt to get rid of them I started dosing vodka about 2 months ago and didn't notice any change in my parameters.
About 2 weeks ago I started dosing with AZ-N03 Absolute zero nitrate and Micro bacter as well. As the algae was growing and killing some of my coral frags. I also added Chemi pure to my canister filter.
I had been testing with API which I know is not very reliable and got about 40 for Nitrate and .25 for phosphate. My LFS usually got my nitrate at between .4 and .12 and phosphate always at .05.
I recently got a hanna checker for phosphate and have been getting it at .02 to .07.
Is it the additives I've been putting in or is something else going on with my tank?
I am going to stop dosing the Az-N03. Should I also stop the vodka and micro bacter?
I had been doing 15% water change every week, but lately doing a gall a day trying to get levels down.

I have a protein skimmer, canister filter and about 50 lbs of live rock, my lights are Orbit Marine Pro Leds.

Any help or advice would be greatly appreciated, thanks.

 

[Wilsoni]

I would ease off but probably not completely stop immediately unless you're experiencing a bacteria bloom.

I have a few questions... What substrate are you using? Is it a DSB? Have you tried vacuuming it?

You mentioned you're running a canister filter, what media do you have in there? They're notorious for being nitrate factories unless you frequently clean them... Also is your skimmer up to par?

 

[Wilsoni]

I don't have first hand experience with Az-N03 so I'm not too familiar with it... Vodka/bacteria dosing are fairly safe if you're conservative and don't overdose them but it would be much smarter to wean off the vodka if you choose to discontinue carbon dosing.

Tell us more about your tank. Do you have coral or is it fish only? Is problem algae the main reason you're trying to get the nitrates down?

Sorry for all the questions, I'm just trying to gain a better understanding.

 

[skipb1956]

I would ease off but probably not completely stop immediately unless you're experiencing a bacteria bloom.

I have a few questions... What substrate are you using? Is it a DSB? Have you tried vacuuming it?

You mentioned you're running a canister filter, what media do you have in there? They're notorious for being nitrate factories unless you frequently clean them... Also is your skimmer up to par?

I used live sand about 1/2 to maybe 2 inches in some parts. I do vacuum it when I do water changes. I was cleaning my filter twice a week as Fluval recommended but about a month ago started doing it once a week as it never seemed that dirty.
The bottom is some kind of black sponge, middle is bio filter, top had a polishing pad and carbon which I just replaced with the Chemi pure, also side has 4 filter pads. My skimmer is an Aquamaxx c HOB which I've never been to impressed with, I'm always adjusting the collection cup as I either get watery skim or none at all.

I would ease off but probably not completely stop immediately unless you're experiencing a bacteria bloom.

 

[skipb1956]

I don't have first hand experience with Az-N03 so I'm not too familiar with it... Vodka/bacteria dosing are fairly safe if you're conservative and don't overdose them but it would be much smarter to wean off the vodka if you choose to discontinue carbon dosing.

Tell us more about your tank. Do you have coral or is it fish only? Is problem algae the main reason you're trying to get the nitrates down?

Sorry for all the questions, I'm just trying to gain a better understanding.

Its a mixed tank with coral and fish and yes I'm trying to get rid of the algae, green hair and now green mat. Now its just the 2 clown fish left. As I said its been doing fine, all looked healthy and happy just the algae was unsightly. I ahve an MP10 and 2 Scicce powerheads so I think my flow is good, but maybe I should add another powerhead?

 

[recess62]

Hmm. A few weeks ago I had a nitrate problem. The nitrate level was off the charts. I dose with amquel plus a nitrate removal solution. My tank crashed: my orp plummeted to 200 and I lost many corals

I do t know if what you used is similar but the literature I just read said to monitor orp. I suspect you had the same issue as I and had oxygen depravation in the tank resulting in the death of the fish. Were you running an air stone ?