Chemistry Questions from a plant/chem noob

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justinb013

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I have been keeping fish for a few years, but just recently decided to start a planted 10G tank. After reading about GH, KH, pH, CO2, P, N, etc. on this and other forums, I decided to go get some test kits and see what was up with my water. The 10G planted tank is a pretty new setup (about a week old) with 3 inches of flourite for substrate, a whisper 10 filter with filter floss (no carbon), a nice chunk of driftwood, and a few basic plants I picked up from the LFS last weekend (elodea, java fern). I've got about 2.6 WPG over the tank (used the AH Supply double brite kit to retro-fit the light strip). I also have 4 little feeder goldfish in the tank to start the cycle, though they will be removed and eaten this week (so I'll continue cycling fishless afterwards). I ran my first set of tests on Friday:

10G

ph = 6.8
ammonia = .25ppm
nitrite = 0 ppm
nitrate = 5ppm
GH = 3 degrees

Either happychem or djlen (you guys rock, btw) then advised that I should also be testing for KH, so I got a test kit for that over the weekend, tested again just a few minutes ago:

10G

pH = 6.4
ammonia = .5ppm
nitrite = 0ppm
nitrate = 20ppm
GH=2degrees
KH=2degrees

The pH and hardnesses seemed low to me, so I added 1/2 tsp of baking soda to the filter to bring them up until I can get some crushed coral as a more long term solution. I intend to setup a DIY CO2 setup once I have the tank more heavily planted and would like to prevent a pH crash.

I was curious why my pH was so low, so I tested tap water that had been sitting out for about 10 hours.

Tap water:
pH = 8.0
GH = 3degrees
KH = 2degrees

Seems to me that the pH in my tank is dropping kind of quickly; however, I'm not sure how fast as I allowed about 3 days in between tests. I'll test again tomorrow PM for better info.

I haven't tested the tap water for nitrates, nor do I have a P test kit yet. I expect a shipment of plants to arrive in the Tue-Thu range, and would like to be able to safely setup the co2 around then. Also by then, the fish should be gone, so I can begin adding liquid ammonia to completely cycle the tank.

I have yet to figure out exactly what sort of ferts I should be dosing. That and what I think is a bit of a pH/KH/GH problem are my current projects... any thoughts, concerns, advice, or requests for more information would be welcomed and entertained.

-Justin
 
You cannot perform a fishless cycle on that tank. If you do, you'll have more algae than you know what to do with. You've got sufficient light, and if I recall that kit correctly, it comes with their reflector, does it? At any rate, you're looking at a rough equivalent of 3wpg when compared to the clunky T12 NO bulbs. So the good news is that you don't need to cycle your tank in the traditional sense.

Read Chuck Gadd's article on setting up a planted tank:
www.csd.net/~cgadd/aqua

And do a search around here for Tom Barr's treatise on a new tank setup. I think that a search for "elephant" should bring you to the right thread. You'll understand when you get there. ;)

Basically, cram your tank with fast growing plants, get the fish out. Give the plants a few weeks to get established, add no water column ferts (you can add root tabs, as long as you don't let DJLen know you're doing it), but while there are no fish in the tank, get your CO2 levels up around 40ppm (if you're doing DIY, go with 2x2L bottles for these first weeks). After a few weeks, slowly bring CO2 down to around 20-30ppm (or 1x2L bottle), then introduce the first couple fish for your stocking plan. Repeat every week or 2 addind the next couple fish for your final stock. With a 10g, this should be pretty quick. You'll never see ammonia or nitrite.
 
Your gH is OK. Your kH must come up to 3.0-3.5(better) and stay there for 5 days or so before injecting CO2.
I would leave the fish in the tank and let the fish and the plants you're going to add cycle the tank for you. This will take only a short period of time.
I would start with 1 - 2ltr. bottle and fish in the tank. This will give the plants the carbon they need while keeping the fish comfortable at the same time.
No ammonia should be used in any event.

You are going to be moving plants around and changing things radically in the next few weeks/months. IMO, there is no use or need for plant tabs of any kind in your tank at any time, but especially at this time. Your plants will not need additional nutrients for weeks. I would not dose anything for now.
Your N levels are high for a few reasons....not the least of which is that gold fish are dirty fish. Feed them very lightly......every couple of days or so....they will be fine.

I wouldn't comment on the pH until you have a better handle on the rate of decrease over a few days time.
Test daily to determine your rate of pH drop, and keep an eye on your kH rise. Any info. you can supply to the forum will aid us in learning your tank as well.
 
Update

Thanks for the info and advice.

a quick update:

Decided based on recommendations to not add liquid ammonia; never considered those points.

The goldfish were exported for breakfast this morning so are no longer an issue. I tested the water about 15 minutes ago and got these readings:

pH = 6.8
ammonia= 0ppm
nitrite = 0ppm
nitrate = 20ppm
GH= 2degrees
KH = 3 degrees

I read at some point that KH test kits may/may not test for actual KH, but for GH instead... I'm using a SeraTest KH test kit. Can anyone expound on this for me a bit?

I would guess the 1/2 tsp baking soda I added yesterday raised the pH and KH. I need to add some more to raise KH a bit more, correct?

I leave the lights on for 10hrs a day at this point.

I spoke with the plant co. and they reported that my plants should be delivered Thursday- they're in central FL and have had to deal with hurricanes Frances and Jeanne.

I've gathered the materials to make 2 DIY co2 bottles with the Jello recipe (if that's still the recommendation) tomorrow or Thu. I plan to pick up a CO2 test kit (useful?).

I posted in an earlier thread that my water was cloudy after initial setup, came to the conclusion that the flourite contributed to cloudiness and that it should clear up shortly...its been a few days and its still kinda cloudy; any thoughts?

I'll hold off on water column or substrate ferts for now. Any other info I can provide that would be of use?

Thanks folks.
 
You need to continue the silent cycle to build your bio-colony.
You've exported all the fish. Fish waste is the most natural top of the cycle chain when building.
What's going to supply the small supply of ammonia that will keep the cycle going?

Len
 
My thinking was that after my plants had had some time to get established, I would add the otos after I brought the CO2 levels down to where the fish could handle it, then gradually add remaining fishies.

Kosher?
 
Looks like you've got it under control.

Skip the CO2 test kit. You can figure it out from pH and KH.

KH test kits actually measure alkalinity, which in most tanks is a pretty good approximation of KH. Check out the thread "the effects of PO4 on KH" in this forum. (shameless self-plug).

I'd skip the jello part too. Do a search on "Tara Nyberg", I like that recipe better.

Get on that crushed coral. I'm assuming your recent 3dKH measure is from the boost from the added baking soda.
 
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