I had the same problem, but mine was just brown and I had white sand, it coved all the plant and decoration, I ordered a product I found, all natural so I tryed it, and it worked great, product name is liquid gravel vac
the one I have is for all marine & reef aquariums,
First I did my water change, the I pulled the plants and decorations and gave them a washing ( you do not have to do this ) It was time for my water change anyway I added the liquid gravel vac and its been 3 weeks and my tank looks wondeful, now I am going to order and try the freshwater one. I will copy and paste the item discription for and leave the website where I got it
Good Luck mercey
LVAC Marine 16oz Liquid Gravel Vac (Tropical)
Item Number: TR0022
Liquid Gravel Vac utilizes the natural sciences of aquatic environmental chemistry to formulate this powerful, one-of-a-kind product. One of the key components is billions of Mother Nature's own "housekeepers": aerobic heterotrophic bacteria. These little overachievers provide all-natural stress free removal of detrimental aquarium pollutants such as uneaten fish food and fish waste through healthy bio remediation. No more accidental bruising or breaking your fragile marine life such as corals, anemones or starfish with the siphon tube. Helps to prevent accidental suffocation of your biological filter by eliminating oxygen consuming, dead and dying organic matter. This product is 100% chemical free. Effectively cleans: gravel, substrate, filtration systems, lift tubes, hoses, ornaments, plastic plants, protein skimmers and other filtration accessories. Treats up to 950 gallons.
Instructions:
Shake well, add 1 tsp per 20 gallons of water. Sludge layers should begin to dissipate within 24 hours. If water is excessively dirty, do a 30-40% water change and add one tsp of liquid gravel vac per 20 gallons of water every other day until water begins to dissolve. We recommend traditional gravel vacuuming be performed once or twice a year.
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