fixing my ph: what's the best approach

[knighto4]

Hi,

I've got a mbuna tank and my pH is dropping. Here are the results:

11 Nov 2011 - 7.6
25 Dec 2011 - 7.0
27 Dec 2011 - 6.0

Did a water change yesterday, could this be why it's dropped so suddenly? I've got ocean rock and crushed coral sand, so I didn't expect pH issues. Added 6 live plants a couple of weeks ago - they really improve the look of the tank, but could they be the cause of my pH problem? Don't want to start adding chemicals, is there another way to fix this?

Advice appreciated.

Thanks

[circlege]

You're experiencing pH drops, and I'd say buffering is the way to go. I've found baking soda to be a reliable solution - it's inexpensive and gets the job done. To raise your pH, I'd recommend adding 1 teaspoon of baking soda per 5 gallons of water. This should bring your pH up to around 8.2. However, be cautious and make these adjustments gradually; it's generally advised not to increase the pH by more than 0.3 per day to avoid shocking your tank.

[medic23]

To rule out any potential causes, I'd like to ask: is there any wood present in your tank? Some types of wood can leach organic acids, which may be contributing to the pH drop.

Also, what's the condition of your tap water? Is it soft and acidic? If so, this could be affecting your pH levels during water changes, and it might take some time for the pH to stabilize again. If that's the case, you might consider using a bicarbonate-based solution, such as bicarb or a calcium/magnesium carbonate/bicarb mix, to help stabilize the pH. Alternatively, you could try aging your water with crushed coral or similar media before water changes, although this would require more space.

If it's not the tap water, then organic matter is likely the culprit, and the live plants you recently added could be a contributing factor. However, there are many variables at play here.

My general advice is to only make adjustments to your water that you're willing to maintain in the long term. This will help ensure a stable environment for your tank.

[knighto4]

Hi Dr Rob & Benzenering,

I've double-checked and can confirm there's no wood in the tank. As for my tap water, it's actually coming out at 7.6, which seems to rule that out as a cause. The plants are looking more and more like the likely culprit. I've read they're good for breaking down nitrates, but how effective are they really? Are they worth the hassle, or would I be better off removing them to avoid messing around with bicarb all the time?

[daxton]

Based on what you've said, I think the plants are the culprit behind your tank's dramatic pH drop - 1 point in just 2 days is a big change. What's your tank's stocking like? I'm guessing the fish aren't too thrilled about the situation right now. If I were you, I'd remove the plants ASAP. Real plants do help with nitrate levels, and in an ideal setup, they can even bring nitrate levels down to zero. However, they're not the best choice for a Mbuna tank, as these fish love to dig and will likely end up eating the plants. If you want a similar look without the hassle, consider using silk plants instead. I've got a few in my Mbuna tank, and they look pretty realistic without causing any water issues.

[axiom]

Plants aren't the main culprit behind your drastic pH drop. Before you start adding buffers like bicarb, I'd advise you to figure out why your pH is crashing in the first place. Test your tank's KH and GH, and compare the results with your tap water. If your KH and GH levels are low, that's likely the reason behind the pH drop. In that case, adding Epsom salts and a bit of bi carb would be a better solution. However, if you start throwing buffers into the mix without understanding the root cause, you risk making your pH fluctuate wildly, which is far more hazardous to your fish and could lead to some, if not all, of them dying. As others have mentioned, once you start using buffers or bicarb, you'll need to keep using them during water changes, so make sure you're prepared for that commitment.

[knighto4]

Hi all,

Thanks for the advice, I really appreciate it. I've taken on board what you've all said and I'm going to try and get to the bottom of this pH issue. My current test kit is a bit limited, it only tests for pH, Nitrate, Nitrite and Ammonia, so I'm a bit stuck when it comes to measuring KH and GH. To be honest, I'm not even sure what these are, so I'll have to do some research.

I've removed the live plants from the tank, so I'll test the pH again in the morning and see if that's made a difference. It's definitely worth noting that my tap water is coming out at 7.6, so it's not that which is causing the problem.

I'm now considering using silk plants instead, has anyone got any recommendations for good brands available in the UK? I've had a look online and some of them seem really good, but I'd love to hear from someone who's used them.

Thanks again for all your help.

[axiom]

How many plants were in your tank, then? Getting a handle on KH and GH is pretty key for a rift tank setup, might be worth looking into an API GH and KH test kit to help you figure out what's going on.

[flair9]

You've got a classic case of old tank syndrome. This is what happens when your tank's buffering capacity is low, and there's a buildup of organics. It's not just the plants, it's a combination of factors like poor maintenance, overfeeding, and underfiltering that lead to acidic processes. The conversion of ammonia to nitrite is one of the main culprits, and it's what makes the water acidic, causing the pH to drop.

I'd recommend daily small water changes to prevent shocking your fish, and eventually, a complete water change, along with a thorough clean of the debris and filter. These can harbor a lot of organics that contribute to the problem. What's your nitrate level, by the way? High nitrates are usually associated with this condition.

Also, keep an eye on your ammonia levels now, as the beneficial bacteria can die off in acidic water. Although it's not as toxic to fish at low pH and temperatures, when the pH starts rising again with water changes, the ammonia can become toxic. So, make sure to monitor that and keep it under control with regular water changes.

Adding baking soda now would be a mistake, as it can cause a sudden pH swing, shocking your fish and leading to a toxic ammonia conversion. I'd advise against it until you're sure you're dealing with low KH and not old tank syndrome. And, by the way, the plants are not the cause of the pH crash, so I'd suggest putting them back in the tank.

[daxton]

I feel I may have jumped the gun with my previous advice. I took it for granted that the KH and GH levels were fine. Given the plants were the only recent addition, I assumed they were the likely cause. As someone who isn't too familiar with aquarium plants, I've had experiences where people have introduced non-aquatic plants that can harm water quality. Lesson learned - I'll ask more questions before offering advice in the future.