Dialing in your Water Quality

Water quality is vital in zebrafish labs as it’s deeply interconnected to aquatic animal husbandry. Less than ideal water quality can affect the overall health and performance of zebrafish. As a research organism, zebrafish are invaluable to scientists and researchers with an important job to play, therefore their health should be a number one priority. Ensuring your fish remain in optimal health can translate into a an all-around, highly productive facility and smooth research operations. There are many aspects of water quality that can be refined (e.g., filtration – which then can break down into biological, chemical, and mechanical components). We’ll touch upon several topics that are worth dialing in and monitoring in your lab to help ensure your fish remain fit.

1. pH

• Maintaining a stable pH is critical in keeping your fish happy, healthy, and performing well (in terms of breeding). Having a stable pH is almost more important than the value itself (as long as it’s within the optimal range, 7-8). Natural bodies of water in the wild regulate pH well, partially due to the fact they’re so large, whereas it can be a little more finicky and difficult to maintain in much smaller, artificial rack systems.
• Closely monitoring pH with sensors and controllers that can adjust dosing to the right conditions is one of the best ways to stay on top of your systems. Many of our installations and projects involve setting up a control panel that includes sensors, calibrations, and dosing for pH, conductivity, temperature, and more. It’s a great investment that both the fish and technicians will thank you for.
• Other inter-related parameters (such as nitrates, nitrites, and ammonia) should always be of high importance as well. Nitrite and ammonia toxicity are amongst the most common issues. Having a reliable water analyzer to check statuses on a weekly basis and developing good husbandry practices will ensure water quality remains up to par.

Best Water Quality Analytical Instruments for Zebrafish Facilities

• One of the better instruments to measure key water quality parameters we’ve found is to be the LaMotte WaterLink SpintouchFF. Reasons being – compact, quick & precise, one of the most trusted & reliable brands, and measures up to 8 key parameters within 2 minutes. It’s the water quality device we use in-house to analyze our water quality samples and have found it to be one of the most effective, intuitive instruments out there.

2. Overfeeding

• One of the primary culprits that can lead to degraded water quality. If less than ideal water quality is persisting or you find yourself cleaning your tanks too much, overfeeding could be playing a part. Using a mechanized fish feeder can be one way to have more control over the amount of food that is being dispensed into the tanks. Another solution is occasionally using a sludge removing bacteria, but we recommend attacking the issue more at the source – such as solving a human error or making sure you have an advanced filtration system in place that can keep up with your fish load. We might suggest refining your BMPs (best management practices) with better-controlled feeding mechanisms – and also staying away from squeezing in a blended, liquid into your tanks.
• At Danio Lab, we offer two fish feeders – each with different dose settings based on the number of fish you have per tank. With over 20+ years of experience in the industry, we’ve come across a wide variety of feeding practices and methods, some better than others. We saw a need in the market for a more efficient, standardized feeding procedure, so we developed these feeders, which has proved to be an easy, practical solution.

• Browse our fish feeders:

ZF TWO Zebrafish Feeder

3. Chlorine

• Contaminants such as chlorine, copper, etc. can be very toxic to fish, particularly at acute levels. This is why employing proper procedures to dechlorinate such as water treatment via RO and using deionized water is the norm.
• As with other parameters, you can usually diagnose the cause by looking at potential fish symptoms, such as in this case – inflamed gills (seen by red coloring.)

4. System Design

• A very broad topic however it’s probably one of the more important aspects to consider when building, updating, adding, or fixing a system. This could include all of the integrated elements in a zebrafish system or more individualized components such as a biomechanical filtration upgrade or the type of UV sterilizer you have in place to purify your incoming water.
• The housing system and filtration design you buy or build to support your fish can have short and long-term effects on your weekly, monthly, and yearly maintenance responsibilities – such as its effectiveness on controlling and maintaining your systems’ water quality. Investing in a well-thought-out system that is superior quality, intuitive to use, and modular for potential changes/scalability are important factors to consider.

5. Dissolved Oxygen

• Aquaculture systems should be engineered to maintain proper levels of dissolved oxygen (DO), although it is still an important variable to keep an eye on as it can be responsible for mortalities. As the number of fish per tank, feeding practices, and system flow affect DO, it should remain near saturation.
• Having a reliable probe with an external monitor – ideally integrated into an automated system is one of the most convenient ways to monitor. Our systems include DO and all other water quality parameters into a centralized control panel, that can be easily used by all lab members of any experience level.

Contact us for service, support, training, or consulting needs regarding your water quality parameters or zebrafish systems. We offer in-house water quality analyses, water quality instruments to purchase, zebrafish housing, zebrafish filtration skids, and more.

[email protected]

Danio Health