How often to change water during cycling

by **Zambize4899** » Mon Mar 24, 2008 2:19 am

I have a new 28 gallon tank. I already have issues with high pH, and I understand that a water change causes the pH to rise, while letting water age in the tank lowers the pH. But I hear that the more frequent changes the best. I'm confused. How often do I change the water in this tank? It is in about the 6th week of cycling, has a biowheel filter, is heated to 80 degrees, and currently has 4 guppies, 2 Swordtails, and one African Dwarf Frog.

My last water test (this morning) showed 0 Ammonia, Nitrate 40 ppm (safe), Nitrite 10 ppm (danger), pH 7.2 (not high today), Hardness 300 (we just have really hard water).

I was changing 25-50% 1-2 times per week, but if it's going to cause high pH, I'm not sure about that frequency. (?)

Thanks

by **Peterkarig3210** » Mon Mar 24, 2008 2:48 am

I'm not the total expert on this but since you have no ammonia (good) you don't have to worry about alkaline ammonia toxicity, so if I were you I wouldn't worry too much about a high pH. You could do half and half with distilled water and tap water. The cycling bacteria are mostly attached to filter media and surfaces in the tank so water changes don't remove much good bacteria. It sounds like the tank is cycling from ammonia to nitrites, and there hasn't developed a sufficient amount of the kind of bacteria to convert nitrites to nitrates yet. I would continue with the rate of water changes you're doing now of 2 times a week and if you want to add some distilled water as well it would help with the pH, but it's probably not a big deal. Just use dechlorinating water conditioner and rinse the filter material in the water you take out during water changes to retain a good colony on the filter material. Unless the filter material is falling apart so much that charcoal is falling out you can reuse it after rinsing. Remember to dump the old charcoal and add new and fill as much as can fit. Unless you have live plants you can't over do the charcoal and it'll help remove toxins from the water.

by **miami754** » Mon Mar 24, 2008 2:51 am

40 ppm for nitrates is in no way safe. Anything above 20 ppm is bad and above 40 ppm is very toxic. I do enough water changes to keep the nitrites and ammonia below 1 ppm during cycling. After the cycle, I change enough water to keep the nitrates around 10 ppo or less. You need to monitor what this entails for your specific tank. Also, how high are we talking when you say your pH is high? Most species of fish have a wide pH range tolerance and only really care that the pH remains fairly constant. Consistent pH is much more important than a specific value.

by **Peterkarig3210** » Mon Mar 24, 2008 2:58 am

Miami knows a lot about aquariums from what I've read. It sounds to me like you might be feeding too much. Try feeding less along with the water changes.

by **spongebob4460** » Mon Mar 24, 2008 3:31 am

If you are doing frequent water changes, 2x a week like u say, then the ph should remain somewhere around the ph of the tap water you are using. What is the ph of the tap water, after it has been sitting out for a day?

after 6 weeks you should be cycled, therefore the high nitrates... but from your amount of fish i have to agree with peter that this amount of fish couldnt be producing enough waste in a matter of days to cause such high nitrites... overfeeding is usually the cause.

Do you vacuum really well during water changes? (i don't mean to be assuming, but both miami and peter would emphasize this for me, and i eventually realized i wasnt vacuuming as well as i should be).

Don't worry though, with Miami and Peter here, you are being guided in the right direction, they helped me tremendously when it came to cycling and low ph problems, and now my tank is near perfect.

Keep us posted each day and we'll help u figure it out.

by **Peterkarig3210** » Mon Mar 24, 2008 3:41 am

Wow Spongebob! The more I learn the less I realise I know. At least we are agreeing on most of this.

by **Zambize4899** » Mon Mar 24, 2008 4:12 am

Thank you so much for your thoughtful replies.

1. I said that 40 ppm for nitrates was "safe" because that's what it says on the tester bottle. 0-40 safe, 80-200 unsafe, and that's all it says. But I believe you over some bottle.

2. I just tested some tap water that is 24 hours old and the pH was hard to read but appeared to be around 7.2. I don't know why my pH is suddenly so low, it has been around 8 - 8.5, but now it is closer to 7.5.

3. I use the Bio-wheel filter. I thought I was supposed to leave the blue pad alone. Should I be cleaning it in the removed tank water at each water change?

4. I do think I was overfeeding but just recently starting feeding less.

5. I *think* I vacuum well. I can't stand to see crud in the bottom, but I have no friends who are aquarists and no one to take a look at my tank so I can't be sure, but I get up as much stuff as I can each water change.

So I'm understanding that 1) keep changing 2x a week, 2) be sure to vacuum as well as possible, 3) use great caution when feeding to not feed too much.

One more question....should I use 24 hour old water for this tank? I've been using it for my Betta tanks, but didn't know if I should with with this tank.

by **cyndrine** » Mon Mar 24, 2008 5:58 am

my experience with tanks is this. had a problem previously myself with high nitrites and cloudiness that took a while to clean up.

1. I always leave my water out for 24 hrs before adding to any tank no matter the species in the tank to try and get some of the chemicals all cities add to the water to make it "safe" for us to drink and use.

2. overfiltering is always good. I had one going just good enough but it wasn't keeping the tank clear. I now have 2 filters running and the only problem i have are shy fish when i want to take pictures.

3. I feed once a day what they will eat in 2 minutes. I turn my filters down for this so less of the flakes are sent to the gravel to break down there between vaccuming's of the gravel.

4. I do not plan on weekly changes of the water but i test weekly and if the levels are fine I leave it alone. I found a gravel vac to clean the gravel that actually filters out the crud from the gravel and puts the water back in the tank unless i add a tube off of it. runs on batteries for suction. that way i can clean the gravel fairly often but don't have to take out water if the ammonia, nitrite and nitrate levels are good and low.

and personal experience with the tester kits and personal tanks as close to zero as possible is great. each brand will give you different levels as being safe i have found.

by **Peterkarig3210** » Mon Mar 24, 2008 6:48 am

You seem to have a good understanding of what you're doing, and the motorized gravel vac sounds pretty cool. The only thing that constantly will go up is nitrate. Nitrite and ammonia should get converted to nitrates with the right bacteria going. Without actually seeing the tank I can't think of anything wrong with what you're doing except that you said your nitrites and nitrates were high. The probable cause is over feeding. and could be compounded with under-vaccuming. Try to get the tank so you can do a water change every 2 weeks of 30% while keeping nitrites and ammonia at zero. Nitrate will have nowhere to go and build up over time and it shouldn't get higher than 40 ppm in 2 weeks before the water change. If you can maintain this schedule you may be able to add more fish. Hey anyone! Is there something I'm not thinking of???
PS The tap water that has chlorine in it is treated when you buy dechlorinator for aquariums. This is not so people can drink the water, it's only for fish tanks. You probably knew this but wanted to make sure.

by **spongebob4460** » Mon Mar 24, 2008 8:22 am

No one addressed the biowheel you have... it sounds like from your post that you clean the biowheel and don't touch the blue pad filter cartridge in it? If this is so, this is incorrect. I have this filter as well. You should NEVER touch the biowheel itself, this is where beneficial bacteria grow. The blue cartridge can be cleaned in tank water (the water you pull out during a water change) by shaking it in that water. This blue filter pad will also contain some good bacteria, but I personally remove it and put in a new one every month, as the fresh carbon helps keep the water clearer and smelling better. You don't need to change it this often but you definitely do need to be cleaning this blue pad, not the wheel however.

There is something off, even with overfeeding, if you do two water changes a week, there shouldnt be 40 ppm of nitrates. Best thing would be to literally break down your routine for us, and even how you test the water and with what kit. I had problems and it ended up being with how i test the water, so it might be something as simple as that.

How often to change water during cycling

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