Dirted tank troubles.

[Abiduwhabi]

Hey guys and gals,

Looking for a little input here. So, my wife decided she wanted to be a little guppy breeder. (Basically just buying the pretty colors and letting them go nuts.)

So, I told her that I would set her up a 36 gallon bow that I grabbed at a resent Petsmart sale. Well I talked her into letting me dirt it, and I began my process.
Now, I have dirted a tank before using miracle grow potting mix and have never really had much trouble out of it.

Here's what is going on. I dirted the tank, capped it with some black sand, planted my plants, and filled up the tank carefully with a bowl. I think I'm good from here but I think the next part may be my problem. I had an Aquaclear AC 70 running on my 55 gallon for around 5 months that I decided to put on the 36.

I figured this would be a pretty quick cycle, but still out of caution I decided to feed it ammonia like I was doing a fishless cycle. Well, after like the second day the ammonia was being turned to nitrite to nitrate at a rapid speed. Again, staying on the side of caution I continued this process for two more weeks and did a couple of large water changes to get the nitrates under control.

So, I tested the water. (API master kit, I know that would be a question. )
Ammonia = 0
Nitrite = 0
Nitrate = 10-20
Ph= 7.4 (Same as my other tanks.)

I decide to get some guppies and give them a go in the tank along with around 10 ghost shrimp. They all seemed fine guppies are swimming all over, ghost shrimp are digging around the sand and flying to the top of the tank. I waited around 8 hours, came back fed the guppies they all ate and swam around.

Next morning, all guppies dead, 4 shrimp dead. I start freaking out, and gathered the rest of the shrimp in a bucket. Tested the water again.

Ammonia=0
Nitrite=0
Nitrate = 10-20
Ph 7.4

About the only thing I can figure is that when I set up my other tanks I had to actually wait for the tank to cycle which in turn gives the dirt time to break down the organics or cycle itself. There are a few bubbles come up from the substrate but I figured if my parameters were fine then the fish would be fine.

Does anyone have any input on this?

 

[Mebbid]

Did you use the organic gardening soil or potting soil? From my understanding the potting soil is a big no no because some of the contents aren't fish safe.

 

[Abiduwhabi]

I used Miracle Grow organic choice potting mix, which I've never had a problem with.

 

[jetajockey]

The big difference between potting and garden soil is the particulate size. Garden soil has a lot of sticks and chunks in it by comparison.

If your N tests look normal then perhaps a few large water changes are in order. Organic soil doesn't have any inorganic ferts in it but that doesn't mean its always going to be safe. There could be a totally unknown compound build up at work here.

 

[Abiduwhabi]

I think I'll do 50% today. My main problem is if my normal tests are in good range, how will I know when the tank is safe?

 

[Mebbid]

If there's no live stock in the tank I would probably look at doing daily 100% water changes for a few days just to get whatever is in the water out.

 

[Abiduwhabi]

Aight, so I did an 80% pwc and then a few hours later did a 30% just so I wouldn't upset the dirt so much. Tossed in an activated carbon pack that I've had laying around for a few years, from when I bought the Aquaclear. (Don't ask why I put it in, I just figured it couldn't hurt.)

Parameters looked good this morning, the plants seem to be loving it, and the snails are really loving it. I think I'll just give it a few more weeks for the dirt to get settled in because I'm almost positive that's my problem.