Hi Nitrates??

[Mare100]

Hi Again Everybody

Have another little issue going on that I could use some advice on. Our 55 Gal. fish only tank has been up and running since early November. It's been doing spectacular. I'll give you a little info on the tank itself...as follows:

Setup:

Crushed Coral bed with undergravel filter.
Cascade hang-on filter.
Coralife Super Skimmer
2 AquaClear 50 powerheads (each pumps 270 gph)

Water Changes:

10 gal. every 2 weeks.....using R/O water.

Fish:

1 Clownfish
1 Lunare Wrasse
1 Snowflake Eel
1 Flame Hawkfish
3 Turbo Snails

All along, our tests have been coming in at near perfect. 0 Nitrites; 0 Ammonia, 8.0 pH, 0 Phosphates; and 0 Nitrates.

We recently had an issue with the Skimmer. The "gunk" cup kept filling up with water and it seemed like it just wasn't skimming like it used to. It was doing a fantastic job and we had gunk every day to clean out. Anyway....we gave the skimmer a good cleaning and even took it back to the LFS and they tested it out for us. They said it was working okay. It is still bubbling fine and we aren't having the problem with the water overflow into the collection cup anymore. But to me...it seemed like it just wasn't diong as good a job as it was. My husband called the Coralife people and they said that after a tank has been pretty established...it is normal for the amount of "gunk" being skimmed out to lessen.

Anyway...the problem we are having is that within the past week is all of a sudden....the water is looking "cloudy". It had been crystal clear all along. It looks like someone stirred up the cc bed and there is tiny particles of sediment all over. I've been testing the water every day. The ammonia was a slight bit up 1 day....but that came down after a water change. Nitrites are still showing at 0. Nitrates, however are VERY high. We use a "TetraTest" kit and the reading is coming back at 100 mg/l!

We did a 15 gal. water change yesterday and Ammonia and Nitrites are 0....but the Nitrates are still up there.

Any ideas what could have caused this? Nothing died in there because we don't have much to keep track of. Someone suggested overfeeding. Could excess food cause such a high Nitrate climb?

Is water changes the only solution. If so....how much and how often to get the water back to normal?

Thanks so much for any help and I'm sorry this was such a long post.

Mare

 

[bertoni]

Excess food could lead to a high nitrate level. This article might help:

http://www.advancedaquarist.com/issues/august2003/chem.htm

Water changes typically don't help much. Growing and harvesting a macroalga or getting a better skimmer are two of the more popular approaches.

The water cloudiness might be a number of things. What are the alkalinity and calcium levels? Perhaps some calcium carbonate precipitation is the issue. Also, the cloudiness could be a bacterial bloom.

 

[Mare100]

Thanks Bertoni...

I'm going to go take a look at that article you linked to now.

We don't have tests for Alkalinity or Calcium. We do have a test kit for "Carbonate Hardness"......is this pretty much the same? I'm sorry.....I never was good at chemistry class in school! LOL!

I forgot to mention........we just purchased about 40 lbs. of Live Rock and we want to pull the undergravel filter and convert the tank to FOWLR. Do you think now would be a good time to do this? Or should we wait till we get the Nitrates back down?

Mare

 

[bertoni]

Carbonate hardness is the right test kit, just another name. Make sure it's okay for saltwater.

The UGF might be contributing to the nitrate level. If you're going to pull it, now might be as good a time as any, but that's a fairly major step.

 

[Mare100]

OK.....I just did the "Carbonate Hardness" (KH) test....

The directions said that an ideal level is between 8 - 10 dH.

Our results came in at 7. Does this mean our calcium level is low?

M

 

[bertoni]

That alkalinity level is okay, although I wouldn't let it go any lower. You'll need a calcium test to determine the calcium level. Carbonate hardness measures, well, roughly, the number of CO3-- and HCO3- ions in the water:

http://reefkeeping.com/issues/2006-06/rhf/index.php

 

[Mare100]

WAAHHHHHHHHHHHH!

I just had a flashback to my High School Chemistry class.....!

OK.....I'm going to have to take some time after I get my daughter to bed to read through this stuff.

In the meantime.....As long as the bad stuff like Ammonia and Nitrites are down.....I'm assuming the fish are safe. We might just end up putting the guys into the QT tanks and pulling the UGF and putting the live rock in.

But in the interim....is there anything we can do to clear up the water and get the nitrates down some?

M

 

[Sk8r]

There are several issues in your post: one is 'crushed coral substrate.' Aragonite is better: cc tends to compact after a certain length of time. YOu may want to phase that out over time, cup at a time, in favor of other sand.

More so is 'undergravel filter'. Those are more for freshwater, and I'd advise you simply disconnect the thing and go over to live rock and a protein skimmer. When you get a chance, pull that filter system out and run a 1 micron filter just for a few hours to get the stuff out of the water. It's trouble waiting to happen. Modern reef tanks don't use filters; they rely on live rock, live sand, and a skimmer to take care of waste without the generation of nitrate and ammonia such as particulate filters and undergravel filters produce hand over fist.

It's a serious thing to suggest someone just rip out the sand base and filter and start essentially over, but I think you may be in for a string of preventable trouble with that sand and that filter, imho.

Trust Bertoni, however: he's far more expert than I am, and he'll steer you right.

 

[Mare100]

Thanks Sk8r...

I totally agree about the UnderGravel Filter. We are not too happy with that choice. When we set the tank up, we took the advice of the LFS guy when he said that this is the setup he would use if doing a fish only tank. Don't get me wrong...he is very knowledgeable and has been very helpful to us.

However....the more I am reading and learning the benefits of the natural filtration of the Live Rock, the more I wish we would have gone that route to begin with.

It just seems to me that as you said....the crushed coral is "compacting" and blocking up the UG filter. Now I did hear somewhere that if we were to simply "disconnect" the UG filter....eventually it would get really nasty down there in the substrate and we would have to pull it out anyway.

I'm hoping that if we are very careful........pulling the fish out and into the QT tanks temporarily....we can scoop out alot of that crushed coral.....pull up the UG filter. We have a bag of aragonite that we can put in......and we already have the LR ready to go. We will filter the water as you suggested to get the particles out. My husband is also seriously thinking of putting a sump in at the same time and putting the skimmer down there.

I just want to make it as stress-less a situation for the fish as I can. But I think in the long run....it will be much better environment for them.

Mare

 

[bertoni]

I wouldn't disconnect the UG filter abruptly, since the tank might suffer an ammonia spike. Also, as you point out, there's going to be a very nasty area in that UGF once the flow stops. The QT tank is a fine idea, if you can get a filter going and find a large enough tub.

Is this a reverse-flow UGF?

 

[Mare100]

Yes....we can reverse the flow on the powerheads which would, I'm assuming, "push" the water upward from the UGF?

But wouldn't this just push more icky stuff out into the water that is trapped down in the substrate?

We have a 10 gal. quarantine tank that we keep filtered, heated and essentially "up and running" just in case of emergencies/new fish, etc. Do you think this would be okay size to keep 1 wrasse, 1 clown and 1 flame hawk in until we get the change-over made to the 55 gal.? That's assuming we do pull the filter, put in some sand and LR and give it some time to filter?

If worse comes to worse....we do have the 120 gal. reef tank we can fall back on.

M

 

[bertoni]

If you go reverse flow, the first step is to put prefilters on the pump to catch the debris. That might help with the nitrate problem, although I'm not sure switching the flow now is a good idea.

The 10g tank might be okay for a short stretch, but I'd buy some sort of larger tub. The fish might only need to be in the tank for a few days, but I'm fairly conservative about crowding fish.

 

[Paul B]

You really need to clean that gravel. An undergravel filter run forward is a disaster in a few months. I reversed mine after a few years with no problems and it has been running for over 30 years like that. I would stir up the gravel and use a canister filter to clean the water. I do this a few times a year.
If you want to remove the UG you can do it then. While it is all stirred up is a good time to do a water change.
Have a great day.
Paul