High Nitrate and Alkalinity
I need some advise on my tank. I have a 60gal that has been established for 2 years. In the tank is roughly 20lbs. live rock, 1 tomoato clown, 1 banana wrasse, 1 midnight dwarf angel, 1 blue tang, 8 turban snails, 1 tube anemone. Everyone is doing fine with no signs of stress. I run a cascade canister filtration system. I have noticed that recently my nitrate levels were at 120ppm, nitrite at 0ppm, alkalnity well over 300ppm, ph at 8.0. I have increased my water changes from 5gal a week to 10 for the past 2 weeks, that has helped a little with the nitrates, reducing it to 100ppm, however the alkalinity has stayed the same. I do not use RO water, but filtered water from the house that I let sit for a week (aerated), with prime. I have changed the filter media as well, but cannot seem to get my levels down. Does anyone know what I may be doing wrong? or what else I can do? One other thing is recently I have added marine buffer by Kent to balance the Ph at 8.3.
Any help would be greatly appreciated.
welcome to the forum
can you post more about your tank? feeding, flow, how deep is your substrate and what kind, lights, salt? protein skimmer? and so forth. as much detail you can give will offer us a chance to give that much detail in return.
i see 1 issue to start, 20lbs of live rock and the canister filter. having about a pound of quality pourus live rock per gallon with good flow ( + water changes ) should be enought for your filtration. canister filters trap detritus and debris and cause high nutrient levels. your tap water might contain nitrates right from the tap i recommend RO/DI water.
Thanks for the quick reply. A little more detail about the tank is I feed 1 cube of brine shimp per day, although over the pastfew days I have reduced that to 1/2 a cube per day, as I have seen excess food not consumed, Flow - I have a bar on the outflow of the canister, and 1 power head (max jet 900), Substrate - 3" deep of crushed coral, Lighting - Coralife T5 36" (1 flourescent and 1 Blue Actinic bulb), Salt - Oceanic Natural Sea Salt Mix, No Protein Skimmer. I have never ran charcoal in the canister, it came with a carbon bag, but I have never replaced it. I have used Purigen for the past 1 year, in the canister, and I replace 1 of the 3 filter pads in the past 2 months.
Question - You stated that 1 pound of porous live rock per gallon should be good enough for my filter. My 20lbs consist of half Texas limestone and half porous rock that I used Purple up on 2 years ago. I have good coraline algea buildup on them all. Should I replace the limestone with porous rock and add 40 more lbs.? Just add 40 more lbs?
Some thought I had, were to start using RO water, add algea, as I believe it feeds on nitrates. Other than that I am looking to you all. And I have no idea how to manange alkalinity.
Another question - How often should I chnage the filter media? should I replace all three pads at once? Should I replace the carbon?
This is the canister I run - Cascade 1000 Canister Filter by Penn Plax - Animal World Network
if i was in your shoes this is what i would do.
your looking at investing more money into the tank ofcourse but i feel its well worth it and will allow the tank and livestock to be more successful, feel free to ask anymore questions.
More rock, an extra power head, protein skimmer, RO/ID water, weekly water changes, rinsing the food will not be a problem. Is my canister worthless? Should I keep it ruuning until I replace it with a sump? Are there any good sites on buiding one?. I have not used purple up in over a year, just to start the coraline process.
What do you mena by an area for cheato)?
Thanks for all of your help.
the canister isnt "worthless" and it could work on a FOWLR if kept clean every few days however live rock,sand,flow (a sump+macro algae wouldnt hurt either) and protein skimming is much more of a better filtering method and if done right it shouldnt be hard to acheive 0-5ppm nitrates. you could also clean it out and use it for a freshwater tank or sell it.
cheato is a macro algae thats good for absorbing extra nutrients. you put it in your sump with a light ( i prefer running the light reverse cycle, meaning when your tank lights are off the sump lights are on to lower the ph flucuations)
what is the plan for this tank? eventually corals?
no issues on helping, im glad your willing to learn - feel free to ask anymore questions.
The overall plan is to have this a reef tank, soft corals, anemones, etc. but I do not want to introduce anything else until I get my levels right, and make sure they can stay stabilized. Thanks again. I will get another power head today, add roughly 3-5 punds of live rock this week, do a water chnage with RO/ID water. I will have to wait on the skimmer until next week. Thanks again.
I have reduced my feeding to every 2 days now, I have started to use RO/ID water (2 X 5 gallon water changes now), stopped usiing the marine buffer, as my alkalinity is still high and my PH is just right. I have also added a hang-on refugium with protein skimmer from CPR, in which I have a 3" SB with Calerpa algea in the fuge. I have replaced the carbon and filter pads in my canister, removed 1/3 of my crushed coral in the main tank.
Things left to do: add argonite to main tank, add more live rock (however I am seeing some dyoff from the move). Should I wait on adding rock until I see the coraline start growing again? I am seeing a slight reduction in my nitrates. It is now down to about 80ppm.
I would suggest that you read these articles for a better understanding of your alkalinity and pH issues.
Chemistry and the Aquarium
both by Randy Holmes Farley
If you are "new" to alkalinity discussions, these will probably be very confusing to read. The end result is that you need to also be testing for calcium to maintain a proper alkalinity and pH level. Your tank is a great example of someone who likely has calcium levels under the necessary levels for the Kent buffer additive to properly work. Kent contains calcium carbonates, but you must also have calcium chlorides. I use the Kent marine liquid Calcium supplement for this particular need.
After you correct this issue and both Alkalinity and Calcium are testing within the proper range, then the use of a B-ionic additive would prove useful to maintain the proper levels, but not for adjustments such as the one you are needing. Generally, Alkalinity should be between 8 and 12 dkh for a reef and 10 to 14 dkh for a FOWLR. Calcium should be between 400 and 450 ppm.
I see no problems in adding live rock at this time. Coraline algae growth will occur when you correct the relationship between alkalinity and calcium.
One more thing, pH tests are only helpful if you test at the same time every day. Swings of pH occur each day, within a given range, as a result of carbonic acids in the water which are given off by the living organisms in your aquarium. This changes with the LIGHT CYCLE, so testing at the same time each day is necessary.
You should have questions at this point. In fact, we all should. This topic is crazy complicated.
Photosynthesis is the process where plants utilize the energy obtained from light to convert carbon dioxide into organic compounds (sugars) which in turn feed the cellular respiration process.
Cellular respiration is occurring constantly in the plant based life within the tank. Quite simply, cellular respiration is the process of oxidizing food molecules (sugars) into carbon dioxide and water.
Since the carbon dioxide is being created by the plants all of the time, but is only being processed during the photoperiod (hours of daylight), the level of carbon dioxide in the tank increases during the hours of darkness.
A small portion of the carbon dioxide combines with the water to form carbonic acid. The carbonic acid ions dissociate a hydrogen ion and then remains as a bicarbonate ion. The pH drops due to the presence of hydrogen ions.
So in summary, the constant respiration of plants and algaes in your system releases carbon dioxide into the water, causing the pH to decline. During photosynthesis, plants take up carbon dioxide and the pH increases.
A common means of combating this diurnal pH variation is to place macroalgaes in a refugium, with its photoperiod set opposite that of the display system. This ensures that photosynthesis is occurring in the system at all times and subsequently, carbon dioxide levels maintain constant.
|All times are GMT -5. The time now is 09:37 AM.|
Powered by vBulletin® Version 3.7.4
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0 PL2