Help with 75 gallon cycling

[VBgal]

Our 75 gallon tank was setup with fish April 25, 2009. Added in media from 10 gallon tank we had. Then we added in 25 small fish platys, zebra danios, etc. Also when it was started used Stress Coat and Stress Zyme (still adding in weekly with water changes) Tested daily and got no ammonia/ammonium. We added in more fish since. We were up to 34 fish. Well our first ammonia/ammonium reading was .25 on 5/20/09. I have been monitoring daily. It keeps going up and up but I am not getting any nitrites yet. My pH is 6.0......is this slowing down the process? At this point we are reading 8.0 ammonium (since our pH is only 6) I was told not to alter the pH. Our tap water pH is about 6.4 or 6.6. I do about a 10 gallon water change 2 times a week at this point trying to help. I have not changed any filter media since we started the tank nor have I rinsed it with the water I have taken from the tank. I also only skim above the gravel to remove any debris or waste but never disturb the gravel. I also only feed the fish once a day. Is it just going to take longer with the lower pH? Anything I can do to help things along or do I just have to deal?

Fish list:
5 cherry barbs,
12 various platys
4 neon tetras
4 lemon tetras
2 von rio tetras
6 red danios
1 plecostomus *small

[robflanker]

1) Welcome to the AC

2) What are you using for testing?

3) I think you'll need to bigger what changes. You are doing about 12% twice a week, you'll need to do more than that.

4) Thats an awful lot of fish to cycle with - have you tried reading the cycling threads? They are really helpful

5) pH - you could use a bag of crushed coral in the filter to regulate pH better

6) What are you doing for filtration?

[VBgal]

1) Welcome to the AC

Thanks!

2) What are you using for testing?

API Freshwater Master test kit

3) I think you'll need to bigger what changes. You are doing about 12% twice a week, you'll need to do more than that.

How much should I be taking out at each change?

4) Thats an awful lot of fish to cycle with - have you tried reading the cycling threads? They are really helpful

Actually I have poked around. The box from the filter said 2-3 fish per gallon to start. I actually want to move some out but the 10 gallon had its 10 inches of fish already.

5) pH - you could use a bag of crushed coral in the filter to regulate pH better

If I used crushed coral...would I not have to worry about changing the pH of our tapwater with each change? Do all fish store carry crush coral? I haven't ever looked for it.

6) What are you doing for filtration?

I have 2 Marineland biowheel 350's. Have all 4 filter pads in place. Also using a 20" bubble curtain for some extra aeration.

[Wild Turkey]

You need to be doing a lot more water changes imo, now and after the cycling issues as well. 25-50% weekly is recommended for most tanks.

Take the ammonia/ammonia way down. Do a 50% water change and get it down to around 4-5ppm and keep it there.

Unless you have some nice tests, the test kits arent telling you how much of that ammonia is ammonium. However, some calculators can.

At such a low ph, the free ammonia should be almost nothing, thats why your fish are not dying, in mass numbers. (around .1 free ammonia)

However, if the ph is 7.0 you are talking about more like 1.0.

So, I would hold off on changing the ph as long as possible, whoever instructed you to not mess with the ph was correct imo.

You are correct though, when you add elements to alter the tank's ph, smaller, more frequent water changes are in order

[robflanker]

WT makes some fine points.

The 1 inch of fish per gallon is a terrible rule and should be abandoned. You cannot and should not have ten 1' fish in a 10g. Not saying you do, but just as an example - the appropriate stocking is based more on bio-load (how much it poops) and less on size of fish (tho it can be important as well).

As WT said, 50% water change asap, and you need to do be doing 25-30 weekly. A python helps here, if you havent got one, i'd get one.

See what the fishless cycle thread says about numbers of fish per gallon to cycle. I suspect its not 2-3 fish per gallon