pH in 75 gal goldfish tank

[Jon Morgan]

Hello,
I started up a new 75 gallon tank the first week of June. It went through the normal cycles, and is now quite stable except for the pH.

In the first two weeks, I lost 6 out of 16 starter comets, and had a few cycle of white cloudy water that I left alone for the most part, but have lost no fish in a month, and have crystal clear water.

One other cloudy cycle in July was treated with Kent ProClear, and has not occured again.

I have only used Prime conditioner.
I do 20% water changes every week or two.
It has a double cartridge (large) Whisper filter with carbon.
There is no direct natural light. Fluorescent during daytime only.
There are about 15 small/medium gold fish and one new snail.
All plastic plants, river stone gravel, two driftwood decorations.
I am not using a heater, and water temp is very constant at 75 degF.

Consistent water tests show that Nitrites and Nitrates are low. Total hardness is "very soft". Alkalinity is moderate/low, but pH is 6.0.

The pH has been consistently low, close to 6.0.

I have used an entire 500 ml bottle of Liquid Neutral Regulator 7.0 in a two week period. No change.

My local pet store strongly recommended the LNR product to me, and is surprised at the lack of change in pH. Is there a detail that I am missing, or should this work for me?

I just bought another bottle ($15) of LNR 7.0, and put 150 ml in today, and will test later.

thanks for any feedback. Sorry for the long post, but I wanted to include all information for your consideration.

[Tech Support CH]

A 500 mL bottle of Neutral Regulator will provide 3.3 doses into your
75 gallon. When there are a lot of organics (waste) built up in the
aquarium than it can take more Neutral Regulator than the normal
dose. With 15 small / medium goldfish a lot of waste is being
produced. If they average only 3 inches each that is a total of 45
inches of fish. With goldfish it is recommend to have at least 2
gallons per inch of goldfish. So 15- 3 inch goldfish require 90
gallons. Neutral Regulator will be able to raise the pH put it is
going to require more doses. I would recommend the powdered version as it is a lot more concentrated. And you can add a dose a day until your pH is raised to the desired level.


The driftwood is also fighting against you. Driftwood releases tannic acid. This lowers the pH. You will be able to keep the driftwood as long as you use enough doses of Neutral Regulator to overcome the acids it produces.

[Jon Morgan]

Great feedback - and quick. thanks CH!

The driftwood was already used in a previous freshwater tank for 5 years or more. I assume the effect would have leveled off or stopped in that period of time. We have tannin-rich river systems here in the Carolinas, so I am familiar with the visual effect it can have, and I see no tannin color in the tank.

I'll buy the powder version of NR 7.0 and will also take out several of the comets to balance the tank fish-load per your recommendation.

thanks again,
JM

[Tech Support CH]

You are very welcome. Although you do not see any tannins they are still releasing a small amount. It is not enough to worry about though.

Good luck and let us know how it goes.