Going On Holiday- Nitrate Level Worries!

Carp4U · Aug 9, 2010

I'm going on holiday on Thursday for 2 and half weeks. My 15 gallon Juwel Rekord 70l tank has a few live plants (getting more tomorrow), not overstocked, and has been running for over 2 years. I bought a test kit for the first time in months yesterday, everything else was okay on the scale except the nitrATE was very high, and was in the area on the scale recommended to do a water change. NitrITE is at zero. I haven't lost any fish recently although the fish seem a little sluggish. In the past on tests the nitrate has been relatively low. I don't know how long I've had high nitrate for. I cleaned it out on Friday, 20% water change, cleaning the filter sponges in the tank water not tap water, and when I noticed the high nitrate I did another 10% change today. I haven't tested the water since.

I won't be here to do my usual weekly 20% water change, and having a nitrate problem already isn't good.
What should I do? Should I carry on making water changes before I go away to make up for the ones I miss?

coldcazzie · Aug 10, 2010

When you say "high" what exactly do you mean in terms of real numbers. Nitrate is a difficult one to judge - some people like to have it as low as possible just to make there are no adverse reactions, but there seems to be a wealth of personal experience which says that even the most sensitive fish can manage just fine in nitrate levels up to several hundred ppm. My personal experience goes along with that, although that's not to say that it's in the best interests of the fish's health - just that they don't show very adverse reactions like gasping at the surface as they would with a nitrite spike or whatever.

In my personal opinion, you don't need to worry about it until you get back from holiday.

And once you get back, to get your nitrate level down to near 0 you need to do an almost complete water change (as near to 100% as possible) because then your tank will only have the nitrate level of the tap water. 10% changes are good for weekly maintainance, but no good for reducing levels - if you think about it in terms of the maths, if you've a nitrate level of 100ppm (for a nice round number) and you change 10% of it for tap water which has 0ppm nitrate, then you have removed 10% of the nitrate in your tank. Which still gives you a nitrate level of 90ppm, which is nearly the same as you started out with. Whereas a 60% change would leave you with a nitrate level of 40ppm. The only time I wouldn't recommend that is if you've not done any water changes at all for a while (ie, several months), in which case daily changes of 25% for a week or 2 would have a similar effect. But if you've been cleaning it regularly then I would say leave it until you come back from hol, then do a 80% change and test again. Someone else might have a different opinion, but that's what I'd do.

Carp4U · Aug 10, 2010

High- as in 250ppm. I don't want to reduce too quickly because the fish will be used to the high nitrate level by now.
Going to do a 10% water change every day before I go on holiday.

Rainbow67 · Aug 10, 2010

Carp4U said:
High- as in 250ppm. I don't want to reduce too quickly because the fish will be used to the high nitrate level by now.
Going to do a 10% water change every day before I go on holiday.

The trouble is doing a 10% water change isn't likely to have too much impact on your nitrate levels.
If you really want to get your nitrate levels down then you need to do much bigger water changes....certainly much bigger than 10% any how.

As long as you Ammonia and Nitrite levels read zero then I would think you would be fine to go on holiday without worrying unduly about any fish deaths due to nitrate levels.

Miss Dib Dabs · Aug 10, 2010

That is high but as you say the fish are used to it. Have you tested the tap water? Sometimes the tap water nitrate content can be high so it would be worth knowing so you know if you are wasting your time with the changes or not. Maybe when you return adding live plants will help reduce the nitrate levels, so long as they're healthy etc. Not a plant specialist so maybe the ppl frequenting that part of the forum can help more. :good:

P.

Gilli · Aug 10, 2010

If you do a huge water change before you go and only feed the fish a minimum amount while you are away (either by timed feeder or if someone is feeding them for you) all should be well until you get back. Also plenty of live plants will use up some of the nitrates.