Cycling with high nitrate tap water :(

[rjw1875]

Hi All,

I'm currently a few days into a fish-less cycle. Here in Cambridge (UK), the water out the tap is particularly hard and high in nitrate. I'm just wondering what I can do to alleviate it and have a healthy tank, as I've already noticed red/brown hair algae starting to form on some of my plants (assuming) due to the high nitrates.

I have a liquid test kit and i'm currently reading "very dark red" from the tap water (>80ppm). I do have a rainwater collector outside and I can also source RO water from my LFS; is it worth mixing either of these with my tap water 50/50? I know that the rainwater could introduce contaminates and that the RO water has no minerals/buffer etc. Which is less risky?

I have a few plants in there to hopefully soak up some nitrates (more so when the plants are bigger), and a few Nerite snails. Wasn't planning on doing a water change until I can see the tank is cycled.

I'm also adding a tiny amount of food each day to help add ammonia for the cycling (i'm talking 10-20 grains of sand size), plus a weekly dose of Seachem Flourish for the plants, and around a 50% dose of "Interpet Fast Filter Start" every couple of days as instructed for a new aquarium.

One thing I don't understand is when I added the initial water to the tank (around 120ltrs), I used my Seachem Prime dechlorinator which states on the bottle that it "detoxifies" nitrates; but it doesn't seem to have made any difference to the levels. The dose I used for my Prime worked out as 0.5ml per 20ltrs, so I basically added 0.5ml to each 15ltr bucket I had when filling the tank (using about about 7-8 buckets in total). Should I be adding more per bucket/water change? I read that Prime is more than a dechlorinator and can help with things like high Nitrates/Nitrites in the tank.

 

[seangee]

Any de-toxification that Prime does (and there is some debate about whether it does any) is temporary and the effect is claimed to last for 24-36 hours. It does not remove nitrate and will not affect your readings. For cycling you would be far better off following a more controlled apprach as detailed in this link.

The EU limit for nitrates in tap water is 50ppm. Your tests may not be accurate if you are using strips. Until the cycle has established there is little point in testing for nitrates because the nitrate test reads both nitrite and nitrate and adds the two together. Once your tank has stabilised at 0 ammonia and nitrites you can start testing for nitrates. Nitrates in your tap water will not affect the cycle from establishing. While this is happening test your tap water for nitrates, or check your supplier's website to see if they publish the results.

If your tap water does contain high nitrates that can be discussed separately while the cycle completes. There are options depending on what you wish to keep - my own tap water has nitrates at 50ppm which is much too high for fish.

 

[Jan Cavalieri]

It detoxifies ammonia too - but only temporarily - I wish they would clearly explain that on the bottle - when I first read it I was like "why worry about cycling my tank" but when the tank still tested for ammonia and nitrites I was just confused = but the API and stick test treats ammonium just like it''s ammonia and nitrites just the same as it treats the toxic version. I kind of think if you CAN get your tank cycled then your cycling methods will just treat the nitrates in the water the same as if it came from another source. So the bacteria you grow once your tank is cycled will be especially good at removing nitrites. Each one of us has different levels of ammonia and nitrite in our water so each of our bacteria load would look a little different. "The CYCLE" doesn't care if your starting with huge amounts of nitrite or small amounts, it will result in sufficient bacteria to get rid of them because that is what the cycle does. Once way you could mess up your cycle is to get it all cycled and working then instead of just adding 3 or 4 fish you added 15. Or if you cycled with low nitrite water but when you got fish you suddendly switched to high nitrite water - in both cases the bacteria in your tank won't be expecting the new kind of load of that your giving it. I did that once by adding too many fish right after I got my tank cycled (because I was ordering online and trying to save postage) a number of those fish died - I ran out and got a bottle of Tetra Safe Plus (which is like giving your tank a big shot of bacteria). To this day when I cycle a tank I add a bottle of Tetra's Safe tank just to make absolutely sure I have enough bacteria to hanlde the number of fish that I'm starting with - you have to build up the right amount of bacteria over time. So your tank may take longer to cycle just because of the high load of nitrites but when cycling is done you should be confident that you cycled well enough to accommodate the additional Nitrites. Add a bottle of Safe Start if it makes you feel better but just start with a small number of fish to allow your bacteria volume to grow to accomodate the new bacterial load that the fishes brought. Does this all make sense?

 

[rjw1875]

Thanks Jan & Sean. I have used the pure ammonia method in the past but ended up throwing away the bottle as I only needed tiny amounts. I've replaced it this time with a few snails and a some food each day, hoping that will have the same effect.

The question still stands about the nitrates. I did have the water tested by Cambridgeshire Water; they told me that whilst it's high - it's still within legal requirements.

I'm reluctant to throw fish in along with a bottle of safe start; I'd like to build up relatively slowly and keep testing with my liquid test kit.

Sean, you mentioned dealing with high nitrates in your water; how do you do this? Would you advise mixing it 50/50 with another water source i mentioned above?

I have seen some 'Nitrate Pads' for sale too, I'll be looking into those.

I can't be the only one with this problem!

 

[seangee]

If you are planning to keep hard water fish it may be worth looking at nitrate filters. Search for "pozzani" on this site.
Mixing 50/50 with RO reduces the hardness and nitrates by 50% but still leaves higher nitrates than desired at 25ppm. You could adjust the ratio, e.g. 75/25 RO to tap or you could just go RO. Depending on the fish you are going to stock this may require re-mineralisation of the RO water. There are cheaper sources of RO in the UK but the main one has slipped my mind .

My own tap water has nitrates at 50ppm and I have used all of these methods. I have finally settled on pure RO with re-mineralisation where necessary, but this is minimal because I keep only soft water fish. The RO decision was helped by the fact that I also have very hard water.

 

[rjw1875]

Thanks Sean. I'll look at starting with 50/50 RO for now and see if I can see any tangible effect without disrupting the tank.