Hi! I finally have my new 150gal tank set up and cycling. It has been set up now for 7 days and has had
fish in it for 5 days. All my fish are in it because I had no choice. They are all fine and happy. I have two
Cascade 1500 canisters running on it. The readings are all at zero except for the ammonia which is rising slowly over the past 3 days. I do not want to use any ammo locks or stuff like that. I want to try this naturally. However, I did add some stress zyme and probably will again on the 7 and 14 day. I guess my question is ~ when they cycling a tank it says to do a 25% water change every
other day, does that mean a gravel vac change "OR" just
a siphon of water with the addition of new? Any suggestions are welcomed. By the way the tank looks awesome, my fish look more beautiful then before with all the room to roam. Thank you!

just change the water, no need to clean the gravel just yet. By all means remove any waste that you may see but don't go overboard on cleaning.

The natural way would be to do it without fish as naturally they wouldnt be subject to ammonia,nitrite and the such like in the wild.The ammonia is gonna rise to high levels quite quickly in you're tank,and will remain so for some weeks,i would really advise using ammo lock or similar as these products turn ammonia into none toxic forms.No ammount of water changes will rid the tank of ammonia unless you empty it completley every day and refill with fresh water.But to do this would mean removing youre fish into something else each day which would cause more stress whilst you undertook this huge task.Plus the more water changes you do the longer it takes for the tank to cycle,please don't think im having ago just putting a point across,I would use ammo lock for the fish sake,thers no doubt they will get through without but is it right to put them through it?Ino there only fish but sometimes its worth thinkin what if it was you and the fish or indeed any animal was looking after you're welfare!!

timskie ~ I value your opinion and of course I want to do the best for my fish thats why I got them a 150 gal tank.
Anyways, the reason I'm afraid to use the ammo lock or the like is because from what I understand once you use it then you will continue to get a positive reading, the ammo lock never gets out of the tank. How will I ever know the tank is cycled if I continue to get a postive reading. And, at one point won't the reading become a false positive down the line in another month or two? How do you ever get the tank to read right once the ammo lock is used? I am really concerned/confused with all the info out there and I certainly don't want to hurt my fish. Thanks again!

from my understanding...

It transforms the amino into another form of amino that is not toxic to the fish, but is still processed in the filter. So the amino is still being processed by the filter, it is just a different form that is not toxic to the fish. So it stills shows positive on the test because there is still amino in the tank. It is just not a form of amino that you have to "worry" about. Once the amino levels drop it will show that on your test.

One more ? ~ While the tank is cycling should I/must I see a nitrite and nitrate reading at some point ??? So far I do not have one and I'm 7 days with fish in it. My ammonia has been up (not drastically) and has come down although still not zero which I don't expect it to be yet.
Like I already said, I just wanted to know if I need to
see postive readings on the trite/trate to know things are
happening. Thanks again.

Let me explain what goes on in an established biological filter, this may help you to understand what to look out for on how it works. The fish produce ammonia through their waste, urine and also excrete it through their gills. You have various types of bacteria living in your filter. One type of bacteria will process the ammonia and convert
it into nitrite. The next bacteria will do the same and convert it into the less toxic form which is known as nitrate. Nitrate is removed by doing water changes. There are chemicals available that will remove nitrate but I think they are unnecessary.

So when you are cycling your tank, you won't see any nitrite or nitrate reading until the bacteria responsible has actually established itself. I would expect you to start seeing a nitrite reading soon. Amonia readings can get quite high in the cycling process so you have to keep an eye on it, you don't want it to get too high because that can have a serious effect on the fishes health. Just keep doing what you're doing, 25% water change every other day to stop the ammonia getting too high. You will see a nitrite reading at some stage. You should stun steel or ammonia start dropping until it is actually zero, then the same thing will happen to a nitrite. Once you start seeing a nitrate reading, you know you are getting somewhere

Basically keep testing for ammonia and nitrite even after adding ammo lock

The result for ammonia will rise
After a while the result for ammonia will start to fall and the result for nitrite will start to rise
After a while longer the result for nitrite will start to fall
When the result for nitrite is zero you tank is cycled

Thank you everyone for your help. As, of today (7 days with fish in tank) I still have ammonia, although low, no sign of nitrite or trates. My ph is low which I understand is better when you are having a ammonia problem.
My fish are happy and smiling & I just hope them & I make it through this cycling time just the same.

In the next week you're ammonia shud rise alot more and you should start to see nitrite appear.Good luck all will be fine in a few weeks

Update ~ 3 weeks yesterday cycling my tank with fish and still no signs of nitrite or nitrate. I have a small amount/steady amount of ammonia and when you use the grid
of ammonia/ph ratio its in the 0.01 toxicity (sp). I have been doing water changes every other day and some light gravel vac since there is some debri. I have not use any ammo lock because I keeping a good eye on everything and I don't want want false/positive readings. I have a 150 gal
with two cascade 1500 filters which is more then enough
filtration. Even after I do a water change in the am in the pm my levels are all the same. WHEN will something changes, WHEN will I see my biological start happening?
Is it possibly taking this long because I have a fully stocked aquarium? I'm sorry once again but this is
a bit stressful to me. The fish are happy lil do they know thier mother is not, lol.

By doing water changes you are diluting the ammonia which is good because ammonia is bad for oscars and the less there is the less damage it will do to your oscars. There is a downside to doing lots of water changes however, by reducing the amount of ammonia in the water you give the good bacteria less to feed on so it will take longer to cycle, try doing less water changes BUT keep an eye on the ammonia and nitrite levels and if they get too high then step up the water changes. Try carrying on as you are but change a smaller percentage