To Lacerite or not?

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Fish Fanatic
Aug 13, 2004
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United Kingdom
Right then.... I got a 240ltr tank holding 35 beauties. The plants are really struggling so I've invested a wedge in a CO2 system (fitted soon).... Dilema.. I've been advised that I should drain the a heating cable to heat the substrate....put a ton of Lacerite on top of it then gravel..... Is this necessary? Or can I add the Lacerite to my tank without draining it. I'm told this may make it go red and be a waste of time????
I aint got laterite in my tank. Mainly because it was going to cost me over £120 for the amount I needed. If the right plants are selected, they have enough light, and you fertilize them often they will be fine. They will love the Co2 as well. Make sure the suface of the water is as still as possible. I'd turn off any airpumps and get any spraybars to face downward. Surface aggitation will get rid of the co2 that you are trying to put in ;)
Before investing in a CO2 system I assume you've checked other things.

If plants are not doing well, first thing to think of is always light. If your light is okay for the type of plants you are trying to grow, then CO2 is normally the next limiting factor. If your light is wrong, CO2 will make very little difference.

With the right light, the right CO2, and a suitable water chemistry, most plants will grow. The substrate is in my experience, the least important factor, I used to use gravel and had good plants. I now use laterite under swimming pool filter sand and have great plants.

I have tried under tank heat pads and in substrate Dennerle heater cables and have never found they made the slightest difference.

You cannot add laterite to an established tank, at least not easily, it will just form a suspension in the water. You may be able to form a slurry/paste and devise some means of injecting it through your substrate, but it sounds like more trouble then it's worth.
As long as you are adding ferts like flourish for your plants, it shouldn't be necessary to add laterite. With good lighting and CO2 in balance, your plants should do better in time.
Thanks for these. The lighting is fine the plants are just not growing particulary well and need a little help. I think I'll go with the CO2 first and see how that works before draining my tank and adding the Lacerite! Cheers.

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