Crazy nitrite readings after big water change - Aquarium Advice

omgfish · 03-19-2007, 04:34 PM

I've been doing a fishless cycle with biospira for exactly 2 weeks now. Everything has made sense so far. I started dosing ammonia the first day and watched the levels slowly go down. Dosed 3-4ppm whenever ammonia reached less than 1ppm. After 4 days I saw nitrites in the water. Eventually I had a nitrite spike and then nitrites slowly came down to less than 0.25 ppm. I just did a 80% water change in hopes of putting my first batch of fish in tomorrow or Wednesday. I just checked my nitrite level and it is a little more than 2ppm!

How is this possible? I have no nitrites out of the tap. For the water change I used a python and took out 80% of the water. Then I added 1 1/2 capfuls of Seachem Prime (its a 75 gallon tank) to the remaining 20% of the water and filled it back up. If anyone has an explanation or any ideas about this I would love to hear from you. TIA!

**neilanh** · 03-19-2007, 04:57 PM

There's been a lot of speculation on this subject the past few months. I don't believe what you're reading is actually nitrItes, but something that's triggering in that test kit when we get to this stage of a fishless cycle. I can't point you to what it is exactly, but i don't believe it to be actual nitrItes. I suspect, that if you were to test your nitrAtes right now, you'd get a reading of between 5 and 10, depending on how well you see colors. I doubt that to be accurate either at this stage.

What I've found, both through my personal experience with a fishless cycle, and reading what others have experiences, is that we will show readings of NO2 at around 2ppm for several days, then all of a sudden they'll clear up. During this time, the NO3 readings will also be hung in the 5-10ppm range, then all of a sudden shoot up to 80+. You might not get that spike to 80 or whatever (mine actually shot to 120) because you just did a PWC however.

omgfish · 03-19-2007, 05:11 PM

Well I just took a nitrate reading and you were correct, its exactly 5ppm. I assume I'll need to wait to add fish until all of these readings go back to normal. This is frustrating. I was planning on getting my fish this week as the LFS had special ordered some for me. Oh well.

**neilanh** · 03-19-2007, 05:15 PM

Well, that's a debate too. Obviously the safest thing to do would be to wait. However, since it's not really believed these to be actual NO2 readings, the debate is that it's okay to go ahead. It's really your call to make in the end, but I'm sure others will chime in with opinions and experiences as well.

In either case, if you do wait, please remember to continue feeding the bacteria with ammonia to support it until you're ready to add fish.

**Zagz** · 03-19-2007, 09:01 PM

Not having used biospira myself, I am basing this only on what other's that have used it have told me. Biospira is supposed to be added at the same time as the fish, it is designed to give closer to an instant cycle, or at the least, very little cycle. I think it may be possible that the biospira and the ammonia together may be affecting the way the tank is cycling. What kind of test kit are you using? When you did the water change did you clean any of the filter? When did you last dose the biospira? Do you have any of it left? Has it been refrigerated?

omgfish · 03-19-2007, 09:22 PM

I used biospira once at the start of my cycle, and added a little more after I saw nitrites. It was handled properly, believe me, I've read a million posts on this. It was used as my seed material, and I know some people will disagree with me, but I think it has had the same effect as using filter media from and established tank. I use the AP master test kit. My cycle has gone similar to alot of the ones I have read about on this site, just a little quicker. I believe this is because I used biospira, and there was more bacteria content. I'm no expert, but I've been testing my water 2-3 times a day and all readings have made perfect sense up until this point. I took out 80% of 75 gallons of water with <0.25ppm nitrite. I added back 80% tap water (treated with Prime) that contained 0 nitrites. Now I have 2ppm nitrites. Something is fishy. I will let the new water settle over night and test in the morning. Oh, I haven't cleaned my Rena XP3 at all. It has one tray that is full of biostars and ceramic rings, so there should be plenty of bacteria in there.

**Zagz** · 03-19-2007, 09:33 PM

If you have done the biospira as you mentioned then I would guess you are having the same issues as some other members here. I would agree with testing in the morning. The test kit is the same as most of us use. I would go ahead and add the fish if you want, just keep an eye on the parameters. Congrats on having done a fishless cycle!

omgfish · 03-19-2007, 09:54 PM

Thanks! Everyone I've talked to around here told me to just throw fish in and let it go. Even the LFS told me this. It seemed like no one could understand why I wanted to do a fishless cycle. I know my fish will be much more happy that I did it this way. I personally think its easier to do it this way anyway, because I can plan exactly what types of fish I want instead of buying some hardy fish I don't necessarily want and hoping they don't die. This forum has been extremely helpful. I've enjoyed reading the different posts for literally hours a day. Thanks to everyone that make this site possible!

omgfish · 03-20-2007, 10:39 AM

Well, I took ammonia and nitrite readings this morning. The ammonia I dosed yesterday after the water change was almost completely gone so I dosed another 2-3ppm. Nitrites are still right at 2ppm. I am planning on stocking about 10-12 fish this Friday. I'm thinking about 6 red glass barbs, 4 boesmani rainbows, and 2 golden siamese algae eaters. I might also get a snail or 2, but I need to do some more research on some snails that don't reproduce like crazy.

omgfish · 03-22-2007, 11:49 PM

Heres an update. I've tested nitrites the past couple days and they measure at 2ppm every time. I am still dosing ammonia and it is still going down every day like normal. I just did a 50% pwc and the nitrites still measure 2ppm. I am stocking with 8-10 fish tomorrow. I will of course make sure ammonia is 0 when I add the new fish. I'll still be testing the water regularly and observing the fish to make sure they are ok. Any other ideas? Thanks.