Nitrates = 0 (is this cycling?) Plus a Hypothesis

[ggrowney]

I am 4 weeks into my fishy cycle and think its complete (12 g bowfront). However, I don't have any nitrate reading at all (ammonia and nitrite are now 0), too. I do have 6 small-medium plants in the aquarium. Could they be taking care of all the nitrates?

Also, I still have an incredibly dense white cloudiness in the mornings. It goes away after about 4 hours under the lights. My theory, and I would appreciate sceptics or support, is that these are CO2 "breathing" bacteria that out compete plants when the lights are off and then eventually are reduced when the plants "respiration" increases under the lights. Is this reasonable?

[rrkss]

Yes your plants can consume all the nitrates. The white cloudyness is not CO2 breathing bacteria. They are most like heterotrophic bacteria consuming organic matter in the water column. As to why they disappear after 4 hours, I would not know without getting a first hand look at your tank. CO2 consuming bacteria use CO2 to make glucose. Your nitrification bacteria oxydize NH3 and NO2 in order to derive the energy needed to convert CO2 + H2O into glucose. Similar to what plants do except they don't use light for the energy but use molecules instead. Most chemotrophic bacteria are anerobic and use Nitrates or Sulphates as a source of energy to convert carbon sources into glucose. Oxygen is toxic to them so they would not be in your water column.

HTH

[ggrowney]

Are the chemotrophic bacteria also feeding on the same biological material?

Also, I have been advised numerous times that cloudiness of this sort will go away with a more "mature" tank. If so, how would this occur? I assume there will always be biological material in the water.

Is there a good text reference for aquarists like me who are curious about the more technical aspects of what is occuring in the tank, but don't have the direct background (I am not a chemist or biologist, but I understand the explanations of the events going on in the tank)?

[cherrypie]

Still cloudy water? Your tank just refuses to settle! How's the algae problem now?

http://www.skepticalaquarist.com/docs/algae/hazy.shtml

Covers the cloudy water situation well.

Obviously for micro-organisms to thrive they need an abundance of nutrients, the problem is figuring out where those nutrients are coming from and how to control them. It's seems plausible that your water supply has a high amount of nutrients, it looks like your nitrogen cycle has established so you can back off on water changes now and go to a regular sort of schedule (ie. 25-50% once weekly). Keep an eye on the ammonia and nitrite levels during this time, just to make sure the cycle is established. Hopefully, if your water is the major nutrient source the combination of the plants and the bacterial bloom can asborb enough nutrients for the bloom to exhaust itself. If you get another bloom following a water change, you can be pretty sure your water supply is the nutrient source.

My guess with the lighting is that it's a case of when the lighting is on, the bloom has to compete with plants and algae, the nutrients get close to exhausted and the population crashes. This would point to them getting a regular injection of nutrients, if you have been doing nightly water changes while getting your cycle established, this would make sense. The other thing that is a likely possibility is that your food is the nutrient source, which would also create a nutrient pulsing effect.

[ggrowney]

Thank you for the link. That is a neat site.

Algae is always growing, but I figure it is a fact of life for a while.

I tested again tonight and had zero readings for all three N's. I wonder if there is any connection with pH. My pH read 8.8 tonight. I took some water out and replaced with some pH neutral distilled water. I know this is not recommended, but my fish are made of iron and I thought it would be interesting to see what happens.

On this topic, I have gotten advice that distilled or RO water is unsuitable for fish. What puzzles me is that marine aquarists use it exclusively. Does the salt and minerals in saltwater make up for what is lacking? If so, are there simple additives I can put in pH 7.0 water to reduce the nutrient level in my tank?

[cherrypie]

Marine salt is fomulation of all salts and trace elements you'd find in ocean water so it has all the mineral requirements of marine life well covered, therefore mixing with distilled/ro water is fine and often preferable.

With your water we originally thought it was soft and slightly acidic based on your initial strip tests (which turned out to be a long way off what your AP kits are giving). Now knowing your pH is that high, it would infer the water is at least somewhat hard, algae and plants may be be helping to raise the pH by scavenging the majority of CO2 in the water during the time the tank is under lighting. If you could do a pH test first thing in the morning before the tank lights come on, the results would be interesting. Also a pH, ammonia and nitrate test of your tap water (after it has been dechlorinated and left to settle overnight) would be of interest. If the pH is high out of the tap, and high in your algae filled tank first thing in the morning you should be fine diluting with distilled/RO water. A hardness kit would give a better idea, but we can make the most of what we have at hand and save you buying too many kits for now, seeing you're just getting started out. If you do want to get one, I'd once again suggest AP's one as it comes with both GH and KH tests, most companies sell them seperately, both have their uses.

As to if you could use straight distilled/RO water and add some sort of concentration containing all the essential electrolytes and trace elements. There's probably something on the market, but I would approach it with plenty of skepticism, the market for such an item wouldn't even be a small percentage of the marine salt market and I wonder how much research would be invested in such a formulation. Diluting your supplied water is likely a more sensible choice.

Also something that may provide more info is to phone your water supplier and ask if they're able to supply a breakdown of the mineral content in the tap water they supply to you. Roan mentioned water in some places over there coming out of the faucet with high phosphates. I looked into it a bit more as nobody answered me as to why, they're apparently part of compounds used in chloramine treated water to stabilize pH and as a corosion inhibitor. Your water supplier should be able to give you some idea as to the concentrations expected.

Personally, In the same situation I'd sit back, keep an eye on my ph, ammonia, nitrite and nitrate levels and hold off on the next water change for a while unless neccessary (btw, with an algae bloom, nil readings on nitrates makes sense). If the main source of nutrients for the algae and bacterial blooms is your tap water, there has to be a population crash sooner or later.

One last thing, I know I keep bringing the subject of feeding up (sorry to be a pain), this is all about nutrient control so it's fairly important. What are you currently feeding your fish? how often? and how much?

Unfortunately your situation has proven to be one of the more difficult ones, with a bit of luck some others will tune in and offer their thoughts also. Not one of us can know everything, but together we're a wealth of ideas and information.

[ggrowney]

As far as this being frustrating, it is not too bad. My tank appears to be fundamentally cycling and working. The cloudiness is more or less a cosmetic frustration as is the algae (which was better today). I have been feeding 2 pellets every other day. Although I did do it every day the first week (before reading). The addition of the distilled water has cleared the appearance some (not completely). The fish seem to be doing fine (btw, I added 6 neon tetra's this week - assuming that is Ok now that the tank has cycled). There hasn't been any ammonia spike thus far.

I will test my tap water and do some research and let you know what I find out.

[Roan Art]

Roan mentioned water in some places over there coming out of the faucet with high phosphates. I looked into it a bit more as nobody answered me as to why, they're apparently part of compounds used in chloramine treated water to stabilize pH and as a corosion inhibitor. Your water supplier should be able to give you some idea as to the concentrations expected.Sorry about that, cherrypie. I must have missed that question in the thread.

Roan

[rrkss]

If you want a more detailed answer, phosphate buffers are used. They are perfect for the use of chloramines since the phosphate buffer system tends to maintain a pH of 7.2 which allows most of the chloramines to remain in the monochloramine form (NH2CL) which is the best form of this compound for disinfection purposes.

[rrkss]

Are the chemotrophic bacteria also feeding on the same biological material?

Since they still need carbon, they will feed on any source of carbon they have access too. They will not cloud your water and being anoxic bacteria, they are rather slow growing and will die in the presence of oxygen.

[cherrypie]

Sounds like you have been on the right track with the feeding regime and if you've been keeping that up for a week or so, I doubt that it's the major source of nutrients and it probably wont hurt too much to feed them a little more. Water supply is seeming like the prime suspect now, so if your water supplier will part with some information for you, that will be a major help, concentrations of phosphates will be of particular interest. Once we know what the deal is with your water, we can figure out where to go from there.

@Roan, bah, don't worry that you missed my Q, you can't be in all places at once ;) Google turned up some quite detailed answers and some interesting reading.