​How hard is it to keep Marine Fish?

“I’ve been keeping tropical fish for years and fancy stepping up to marines, but all the forums I see make it seem so hard! What’s the score?”

The truth is that keeping marine fish isn’t hard, but it is more demanding and expensive than keeping tropical or coldwater fish. Before exploring the ins and outs of marine fishkeeping, it’s worth mentioning that the added expense is due to the fact that all the equipment you need has to be designed to work reliably in salt water, has to be pure and chemically stable and tends to be quite advanced. There are a hundred different ways to keep a marine tank successfully, but if you are thinking of doing it on a budget, please reconsider carefully. Investing in the proper equipment up front will help you to enjoy many years of successful marine fishkeeping, while attempting to make do with cheaper equipment often only compromises the welfare of your livestock.

With that being said, there’s no avoiding the demanding nature of marine fishkeeping, but it is not hard! You won’t need a degree in Biology to be successful, but you will need to make sure that all of the necessary checks and maintenance are carried out on time and to an accurate standard, otherwise disaster could strike in a matter of hours. Diligence and regularity are the true measures of successful marine fishkeeping, so if you are often away from home or work strange hours, then you may find it difficult to keep your marine aquarium’s parameters properly balanced.

The size of your aquarium is very important as it will dictate which fish you can have and how many, what corals you can have, how often you’ll need to carry out maintenance and how expensive your setup will cost overall. Filtration in a marine tank is paramount, as is ensuring that your pumps, filters, protein skimmers, bio reactors and powerheads all adequately meet your tank’s requirements.

The crucial part of filtration lies within the Live Rock. We would recommend as a guide that a minimum of 10% of your gross water volume is filled with live rock, so a 200-litre aquarium would need 20kgs of live rock. Without this base level of organic filtration, you may struggle to balance the water parameters in the tank and will find success hard to achieve.

You would then need to consider your lighting requirements, and as this is such a wide-ranging topic, it’s well worth visiting your local Maidenhead Aquatics store and chatting with a member of staff for advice. It’s a virtual certainty that in order to succeed with corals, you’ll need to invest in an advanced lighting system.

Maintenance is obviously the real key to long-term success. Plan for a minimum 10-15% water change once a week, every week, without fail. Regular water changes will help keep pollutants to a minimum but also ensure that the critical levels of essential elements and minerals stay at optimum levels for coral growth. Although some people do use tap water, we can only recommended RO water for marine fishkeeping. RO (Reverse Osmosis) water is readily available from Maidenhead Aquatic stores and will be required for use in your salt mix and for daily tank top-ups, as marine aquariums lose a lot of water to evaporation and this needs replacing frequently. Unsalted RO water is perfect for this task. There are many other small maintenance jobs that need doing daily, weekly or monthly, all crucial to the long-term success of the tank.

All of the general advice above is just the tip of the iceberg, however, and doesn’t even touch upon the decisions to be made around the choice of fish, coral placement, clean-up crews, additives and so on. As with many aspects of livestock care there are several routes to success but although fashions come and go, tried and tested techniques can be relied on. These various factors are all best discussed with a member of staff at your local Maidenhead Aquatics store. One thing is for certain though, is that good investment and due diligence to your tank will help ensure that you have a stunning slice of the ocean that you can enjoy for years.