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Hi All,

I'm trying to get my system through startup and I'm at a loss as to what is happening with the water chemisty.The overall water volume is about 15 gallons and I've introduced just under 30 feeder goldfish in stages. I've been testing regularly with an API Master Kit and gotten pH results are high 7.8, with a just a little ammonia (.25). I've seen nothing in the way of intermediate products (nitrites), but have picked up 5.0 ppm for nitrates. I had previously "seeded" the tank with water taken for the family goldfish tank, to speed things up.

Do I need more time or more fish to get this thing up to a state where I can start growing stuff?



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you didn't say how long the "stages" were for adding the fish.

I'm gonna guess more time to get it completely cycled up as it usually takes about 6 weeks to cycle on average.

But you should be able to go ahead and plant some seeds right away.  5 ppm of nitrate is enough for greens and herbs certainly and it looks like a shady enough position and small enough bed that greens and herbs are probably your best plant choices anyway.


I just ran some tests again this morning and my data is in question. The pH tested as 8.0. which is up from yesterday. I added a capful of white vinegar, re-tested and got 7.8. The nitrites and nitrates came out to 0.0. and the ammonia is still at .25, which makes no sense, given that a number of fish have been in the tank for more than two weeks. The excess food alone should be enough to bring about some kind of change.

I lost two fish over the last two days, but the remaining ones seem lively and are feeding well.

Is there some type of media needed for planting seeds, of can I just place them below the water line, when I finally get nitrates showing?

I will continue to test and record info daily.




seeds can be planted any time.

How long have the fish been in the system?

If you question your water tests you might take a sample to the aquarium shop and get a second opinion.

I have already done so, though they haven't volunteered to to anything other than pH and are using strips rather than a test kit.

I'll test this moring and see if anything has changed since yesterday. Stay tuned.

What test kit are you using Timothy?

The API Master Freshwater Kit.


Here are my results from yesterday afternoon:


pH: 7.8

Ammonia: 1.0 ppm

Nitrite: .25

Nitrates: 2.50 (estimated- the color is darker than the lowest calibrated value on the chart)


I've been adding about a teasppon of vinegar each of the last three times I tested, in order to try to slowly bring the pH down a bit. I know that once the bio-filter gets going, it should start to decline by itself. The question really is: how many fiish do I need in order to get things up and running properly? I know I'll have to replace the ones that have expired, but given the formula amount of 1 lb. of fish per cubic foot (?) of growbed, I'd need about 3.5 pounds of goldfish.

Can I artifiicially enhance my bacteria or speed up their growth rate without harming the fish?


Thanks for all the help.

Timothy,  That 1lb of fish per cubic food of bed is the MAX recommended, YOU DO NOT NEED THAT MANY FISH for the system to operate.  I like to recommend one fish per cubic foot of grow bed and those fish can max out at 1 lb when grown out.

Looks like you are just in the early stages of cycling up.  Quit bothering with the vinegar as it isn't doing anything to help speed up the cycling.

How to speed up the bacteria, as much aeration as possible, as much flow as possible through the filtration, and patience.  Cycling up with fish generally takes 6 weeks, if you do something additional to enhance the bacteria (like bottled bacteria) it might take you half a dozen weeks to cycle up.  When people tell you that they can cycle up in just a few weeks or even a few days, that is generally not very realistic and they still need to watch water quality once they add the fish.


Here are yesterday's numbers:

pH- 7.8

Nitrites- .50


Ammonia- 2.0


The rise in nitrites indicates that there is something in the works. The nitrate reading is, again, a crude estimate on my part (or perhaps wishful thinking).

The question is: how many fish do I need to get this thing up and running optimally? I had an OMG moment yesterday when I caught the video on YouTube that showed how big these fish can get in a growing season. I was just stunned, since I thought they would not increase in size.


At any rate, I added some plants on Sunday and, with one exception, they are surviving. I'll be testing again in a few minutes and hope to see some changes.



I see ammonia and nitrites are up, so that means you have enough fish to get the initial cycle up going.

Relax and with hold feeding a bit since ammonia and nitrite above .5-1 are bad for the fish.

Here is a blog post about cycling up with fish.

If you were to loose all the fish, you can still cycle up fishless.

Once you are cycled up and both ammonia and nitrite are 0 while you are able to feed your fish,

Then you pay attention to how your plants are doing.  If your plants are growing well, then you have enough fish (it doesn't even really matter what the nitrate test reads since it could be 0 and if the plants are doing well, then you are perfectly balanced and all is good.)  If your plants are showing signs of nitrogen deficiency and your nitrate reading is 0, then you need more fish or to feed them a higher protein fish food or both (but only after your bio-filter is fully cycled up and ammonia and nitrite read 0.)

Beware that there are other deficiencies that can affect plant growth so once things are cycled up you will need to look up what the different deficiencies look like and how they affect the plant (what part do they affect first and so on.)


Thanks. I very much appreciate the assistance. I'll hold off on feeding them for the day and see what happens in the morning.

Should I dose the thing with vinegar to get the pH down a bit of leave as is?

I would leave it alone.  The more things you mess with the slower things will tend to go.  Getting cycled up faster the only things I normally recommend are plenty of aeration and plenty of water flow (if doing timed flood and drain you might switch to constant flood for a time as in leave the pump on full time instead of using the timer.)

And here is a blog post that has info in case you need to protect your fish from nitrite.

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